diff --git a/README.md b/README.md
index f6ce37546..c252ad041 100644
--- a/README.md
+++ b/README.md
@@ -1,4 +1,5 @@
 # Cairo Verifier
+![Cairo Verifier](https://github.com/HerodotusDev/cairo-verifier/assets/46165861/8692dfc1-f267-4c7e-9af0-4ceaeec84207)
 
 This document provides steps to build and run the Cairo Verifier.
 
diff --git a/src/common/array_append.cairo b/src/common/array_append.cairo
index a54329f60..74aecb46e 100644
--- a/src/common/array_append.cairo
+++ b/src/common/array_append.cairo
@@ -50,25 +50,21 @@ impl ArrayU32AppendFelt of ArrayAppendTrait<u32, felt252> {
 }
 
 impl ArrayU32AppendFeltsSpan of ArrayAppendTrait<u32, Span<felt252>> {
-    fn append_little_endian(ref self: Array<u32>, element: Span<felt252>) {
-        let mut i = 0;
+    fn append_little_endian(ref self: Array<u32>, mut element: Span<felt252>) {
         loop {
-            if i == element.len() {
-                break;
+            match element.pop_front() {
+                Option::Some(elem) => self.append_little_endian(*elem),
+                Option::None => { break; }
             }
-            self.append_little_endian(*element[i]);
-            i += 1;
-        };
+        }
     }
-    fn append_big_endian(ref self: Array<u32>, element: Span<felt252>) {
-        let mut i = 0;
+    fn append_big_endian(ref self: Array<u32>, mut element: Span<felt252>) {
         loop {
-            if i == element.len() {
-                break;
+            match element.pop_front() {
+                Option::Some(elem) => self.append_big_endian(*elem),
+                Option::None => { break; }
             }
-            self.append_big_endian(*element[i]);
-            i += 1;
-        };
+        }
     }
 }
 
diff --git a/src/common/blake2s.cairo b/src/common/blake2s.cairo
index 8305b16c9..2bad1f728 100644
--- a/src/common/blake2s.cairo
+++ b/src/common/blake2s.cairo
@@ -87,15 +87,7 @@ fn blake2s_init() -> blake2s_state {
         0x1F83D9AB,
         0x5BE0CD19
     ];
-    let mut buf = ArrayTrait::new();
-    let mut i = 0;
-    loop {
-        if i == 16 {
-            break;
-        }
-        buf.append(0);
-        i += 1;
-    };
+    let mut buf = array![0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0];
 
     blake2s_state { h: blake2s_IV, t0: 0, t1: 0, f0: 0, buf: buf, buflen: 0 }
 }
@@ -132,127 +124,85 @@ fn blake2s_compress(mut s: blake2s_state, m: Array<u32>) -> blake2s_state {
 
         // ROUND function begin
 
-        let mut a = 0;
-        let mut b = 0;
-        let mut c = 0;
-        let mut d = 0;
-        let mut i = 0;
-        loop {
-            if i == 8 {
-                break;
-            }
-            if i == 0 {
-                a = v0;
-                b = v4;
-                c = v8;
-                d = v12;
-            } else if i == 1 {
-                a = v1;
-                b = v5;
-                c = v9;
-                d = v13;
-            } else if i == 2 {
-                a = v2;
-                b = v6;
-                c = v10;
-                d = v14;
-            } else if i == 3 {
-                a = v3;
-                b = v7;
-                c = v11;
-                d = v15;
-            } else if i == 4 {
-                a = v0;
-                b = v5;
-                c = v10;
-                d = v15;
-            } else if i == 5 {
-                a = v1;
-                b = v6;
-                c = v11;
-                d = v12;
-            } else if i == 6 {
-                a = v2;
-                b = v7;
-                c = v8;
-                d = v13;
-            } else if i == 7 {
-                a = v3;
-                b = v4;
-                c = v9;
-                d = v14;
-            };
-
-            // G function begin
-
-            // a = a + b + m[sigma[r][2*i]]
-            a = u32_wrapping_add(u32_wrapping_add(a, b), *m_span.at(*sigma[2 * i]));
-
-            d = rotr16(d ^ a);
-
-            // c = c + d
-            c = u32_wrapping_add(c, d);
-
-            b = rotr12(b ^ c);
-
-            // a = a + b + m[sigma[r][2*i+1]]
-            a = u32_wrapping_add(u32_wrapping_add(a, b), *m_span.at(*sigma[2 * i + 1]));
-
-            d = rotr8(d ^ a);
-
-            // c = c + d
-            c = u32_wrapping_add(c, d);
-
-            b = rotr7(b ^ c);
-
-            // G function end
-
-            if i == 0 {
-                v0 = a;
-                v4 = b;
-                v8 = c;
-                v12 = d;
-            } else if i == 1 {
-                v1 = a;
-                v5 = b;
-                v9 = c;
-                v13 = d;
-            } else if i == 2 {
-                v2 = a;
-                v6 = b;
-                v10 = c;
-                v14 = d;
-            } else if i == 3 {
-                v3 = a;
-                v7 = b;
-                v11 = c;
-                v15 = d;
-            } else if i == 4 {
-                v0 = a;
-                v5 = b;
-                v10 = c;
-                v15 = d;
-            } else if i == 5 {
-                v1 = a;
-                v6 = b;
-                v11 = c;
-                v12 = d;
-            } else if i == 6 {
-                v2 = a;
-                v7 = b;
-                v8 = c;
-                v13 = d;
-            } else if i == 7 {
-                v3 = a;
-                v4 = b;
-                v9 = c;
-                v14 = d;
-            };
-
-            i += 1;
-        };
-
-        // ROUND function end
+        // 0 - 0,4,8,12
+        v0 = u32_wrapping_add(u32_wrapping_add(v0, v4), *m_span.at(*sigma[0]));
+        v12 = rotr16(v12 ^ v0);
+        v8 = u32_wrapping_add(v8, v12);
+        v4 = rotr12(v4 ^ v8);
+        v0 = u32_wrapping_add(u32_wrapping_add(v0, v4), *m_span.at(*sigma[1]));
+        v12 = rotr8(v12 ^ v0);
+        v8 = u32_wrapping_add(v8, v12);
+        v4 = rotr7(v4 ^ v8);
+
+        // 1 - 1,5,9,13
+        v1 = u32_wrapping_add(u32_wrapping_add(v1, v5), *m_span.at(*sigma[2]));
+        v13 = rotr16(v13 ^ v1);
+        v9 = u32_wrapping_add(v9, v13);
+        v5 = rotr12(v5 ^ v9);
+        v1 = u32_wrapping_add(u32_wrapping_add(v1, v5), *m_span.at(*sigma[3]));
+        v13 = rotr8(v13 ^ v1);
+        v9 = u32_wrapping_add(v9, v13);
+        v5 = rotr7(v5 ^ v9);
+
+        // 2 - 2,6,10,14
+        v2 = u32_wrapping_add(u32_wrapping_add(v2, v6), *m_span.at(*sigma[4]));
+        v14 = rotr16(v14 ^ v2);
+        v10 = u32_wrapping_add(v10, v14);
+        v6 = rotr12(v6 ^ v10);
+        v2 = u32_wrapping_add(u32_wrapping_add(v2, v6), *m_span.at(*sigma[5]));
+        v14 = rotr8(v14 ^ v2);
+        v10 = u32_wrapping_add(v10, v14);
+        v6 = rotr7(v6 ^ v10);
+
+        // 3 - 3,7,11,15
+        v3 = u32_wrapping_add(u32_wrapping_add(v3, v7), *m_span.at(*sigma[6]));
+        v15 = rotr16(v15 ^ v3);
+        v11 = u32_wrapping_add(v11, v15);
+        v7 = rotr12(v7 ^ v11);
+        v3 = u32_wrapping_add(u32_wrapping_add(v3, v7), *m_span.at(*sigma[7]));
+        v15 = rotr8(v15 ^ v3);
+        v11 = u32_wrapping_add(v11, v15);
+        v7 = rotr7(v7 ^ v11);
+
+        // 4 - 0,5,10,15
+        v0 = u32_wrapping_add(u32_wrapping_add(v0, v5), *m_span.at(*sigma[8]));
+        v15 = rotr16(v15 ^ v0);
+        v10 = u32_wrapping_add(v10, v15);
+        v5 = rotr12(v5 ^ v10);
+        v0 = u32_wrapping_add(u32_wrapping_add(v0, v5), *m_span.at(*sigma[9]));
+        v15 = rotr8(v15 ^ v0);
+        v10 = u32_wrapping_add(v10, v15);
+        v5 = rotr7(v5 ^ v10);
+
+        // 5 - 1,6,11,12
+        v1 = u32_wrapping_add(u32_wrapping_add(v1, v6), *m_span.at(*sigma[10]));
+        v12 = rotr16(v12 ^ v1);
+        v11 = u32_wrapping_add(v11, v12);
+        v6 = rotr12(v6 ^ v11);
+        v1 = u32_wrapping_add(u32_wrapping_add(v1, v6), *m_span.at(*sigma[11]));
+        v12 = rotr8(v12 ^ v1);
+        v11 = u32_wrapping_add(v11, v12);
+        v6 = rotr7(v6 ^ v11);
+
+        // 6 - 2,7,8,13
+        v2 = u32_wrapping_add(u32_wrapping_add(v2, v7), *m_span.at(*sigma[12]));
+        v13 = rotr16(v13 ^ v2);
+        v8 = u32_wrapping_add(v8, v13);
+        v7 = rotr12(v7 ^ v8);
+        v2 = u32_wrapping_add(u32_wrapping_add(v2, v7), *m_span.at(*sigma[13]));
+        v13 = rotr8(v13 ^ v2);
+        v8 = u32_wrapping_add(v8, v13);
+        v7 = rotr7(v7 ^ v8);
+
+        // 7 - 3,4,9,14
+        v3 = u32_wrapping_add(u32_wrapping_add(v3, v4), *m_span.at(*sigma[14]));
+        v14 = rotr16(v14 ^ v3);
+        v9 = u32_wrapping_add(v9, v14);
+        v4 = rotr12(v4 ^ v9);
+        v3 = u32_wrapping_add(u32_wrapping_add(v3, v4), *m_span.at(*sigma[15]));
+        v14 = rotr8(v14 ^ v3);
+        v9 = u32_wrapping_add(v9, v14);
+        v4 = rotr7(v4 ^ v9);
 
         r += 1;
     };
diff --git a/src/common/blake2s_u8.cairo b/src/common/blake2s_u8.cairo
index 9d46538e9..72962a58a 100644
--- a/src/common/blake2s_u8.cairo
+++ b/src/common/blake2s_u8.cairo
@@ -88,15 +88,7 @@ fn blake2s_init() -> blake2s_state {
         0x1F83D9AB,
         0x5BE0CD19
     ];
-    let mut buf = ArrayTrait::new();
-    let mut i = 0;
-    loop {
-        if i == 64 {
-            break;
-        }
-        buf.append(0);
-        i += 1;
-    };
+    let mut buf = array![0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0];
 
     blake2s_state { h: blake2s_IV, t0: 0, t1: 0, f0: 0, buf: buf, buflen: 0 }
 }
@@ -144,125 +136,85 @@ fn blake2s_compress(mut s: blake2s_state, in: Array<u8>) -> blake2s_state {
 
         // ROUND function begin
 
-        let mut a = 0;
-        let mut b = 0;
-        let mut c = 0;
-        let mut d = 0;
-        let mut i = 0;
-        loop {
-            if i == 8 {
-                break;
-            }
-            if i == 0 {
-                a = v0;
-                b = v4;
-                c = v8;
-                d = v12;
-            } else if i == 1 {
-                a = v1;
-                b = v5;
-                c = v9;
-                d = v13;
-            } else if i == 2 {
-                a = v2;
-                b = v6;
-                c = v10;
-                d = v14;
-            } else if i == 3 {
-                a = v3;
-                b = v7;
-                c = v11;
-                d = v15;
-            } else if i == 4 {
-                a = v0;
-                b = v5;
-                c = v10;
-                d = v15;
-            } else if i == 5 {
-                a = v1;
-                b = v6;
-                c = v11;
-                d = v12;
-            } else if i == 6 {
-                a = v2;
-                b = v7;
-                c = v8;
-                d = v13;
-            } else if i == 7 {
-                a = v3;
-                b = v4;
-                c = v9;
-                d = v14;
-            };
-
-            // G function begin
-
-            // a = a + b + m[sigma[r][2*i]]
-            a = u32_wrapping_add(u32_wrapping_add(a, b), *m_span.at(*sigma[2 * i]));
-
-            d = rotr16(d ^ a);
-
-            // c = c + d
-            c = u32_wrapping_add(c, d);
-
-            b = rotr12(b ^ c);
-
-            // a = a + b + m[sigma[r][2*i+1]]
-            a = u32_wrapping_add(u32_wrapping_add(a, b), *m_span.at(*sigma[2 * i + 1]));
-
-            d = rotr8(d ^ a);
-
-            // c = c + d
-            c = u32_wrapping_add(c, d);
-
-            b = rotr7(b ^ c);
-
-            // G function end
-
-            if i == 0 {
-                v0 = a;
-                v4 = b;
-                v8 = c;
-                v12 = d;
-            } else if i == 1 {
-                v1 = a;
-                v5 = b;
-                v9 = c;
-                v13 = d;
-            } else if i == 2 {
-                v2 = a;
-                v6 = b;
-                v10 = c;
-                v14 = d;
-            } else if i == 3 {
-                v3 = a;
-                v7 = b;
-                v11 = c;
-                v15 = d;
-            } else if i == 4 {
-                v0 = a;
-                v5 = b;
-                v10 = c;
-                v15 = d;
-            } else if i == 5 {
-                v1 = a;
-                v6 = b;
-                v11 = c;
-                v12 = d;
-            } else if i == 6 {
-                v2 = a;
-                v7 = b;
-                v8 = c;
-                v13 = d;
-            } else if i == 7 {
-                v3 = a;
-                v4 = b;
-                v9 = c;
-                v14 = d;
-            };
-
-            i += 1;
-        };
+        // 0 - 0,4,8,12
+        v0 = u32_wrapping_add(u32_wrapping_add(v0, v4), *m_span.at(*sigma[0]));
+        v12 = rotr16(v12 ^ v0);
+        v8 = u32_wrapping_add(v8, v12);
+        v4 = rotr12(v4 ^ v8);
+        v0 = u32_wrapping_add(u32_wrapping_add(v0, v4), *m_span.at(*sigma[1]));
+        v12 = rotr8(v12 ^ v0);
+        v8 = u32_wrapping_add(v8, v12);
+        v4 = rotr7(v4 ^ v8);
+
+        // 1 - 1,5,9,13
+        v1 = u32_wrapping_add(u32_wrapping_add(v1, v5), *m_span.at(*sigma[2]));
+        v13 = rotr16(v13 ^ v1);
+        v9 = u32_wrapping_add(v9, v13);
+        v5 = rotr12(v5 ^ v9);
+        v1 = u32_wrapping_add(u32_wrapping_add(v1, v5), *m_span.at(*sigma[3]));
+        v13 = rotr8(v13 ^ v1);
+        v9 = u32_wrapping_add(v9, v13);
+        v5 = rotr7(v5 ^ v9);
+
+        // 2 - 2,6,10,14
+        v2 = u32_wrapping_add(u32_wrapping_add(v2, v6), *m_span.at(*sigma[4]));
+        v14 = rotr16(v14 ^ v2);
+        v10 = u32_wrapping_add(v10, v14);
+        v6 = rotr12(v6 ^ v10);
+        v2 = u32_wrapping_add(u32_wrapping_add(v2, v6), *m_span.at(*sigma[5]));
+        v14 = rotr8(v14 ^ v2);
+        v10 = u32_wrapping_add(v10, v14);
+        v6 = rotr7(v6 ^ v10);
+
+        // 3 - 3,7,11,15
+        v3 = u32_wrapping_add(u32_wrapping_add(v3, v7), *m_span.at(*sigma[6]));
+        v15 = rotr16(v15 ^ v3);
+        v11 = u32_wrapping_add(v11, v15);
+        v7 = rotr12(v7 ^ v11);
+        v3 = u32_wrapping_add(u32_wrapping_add(v3, v7), *m_span.at(*sigma[7]));
+        v15 = rotr8(v15 ^ v3);
+        v11 = u32_wrapping_add(v11, v15);
+        v7 = rotr7(v7 ^ v11);
+
+        // 4 - 0,5,10,15
+        v0 = u32_wrapping_add(u32_wrapping_add(v0, v5), *m_span.at(*sigma[8]));
+        v15 = rotr16(v15 ^ v0);
+        v10 = u32_wrapping_add(v10, v15);
+        v5 = rotr12(v5 ^ v10);
+        v0 = u32_wrapping_add(u32_wrapping_add(v0, v5), *m_span.at(*sigma[9]));
+        v15 = rotr8(v15 ^ v0);
+        v10 = u32_wrapping_add(v10, v15);
+        v5 = rotr7(v5 ^ v10);
+
+        // 5 - 1,6,11,12
+        v1 = u32_wrapping_add(u32_wrapping_add(v1, v6), *m_span.at(*sigma[10]));
+        v12 = rotr16(v12 ^ v1);
+        v11 = u32_wrapping_add(v11, v12);
+        v6 = rotr12(v6 ^ v11);
+        v1 = u32_wrapping_add(u32_wrapping_add(v1, v6), *m_span.at(*sigma[11]));
+        v12 = rotr8(v12 ^ v1);
+        v11 = u32_wrapping_add(v11, v12);
+        v6 = rotr7(v6 ^ v11);
+
+        // 6 - 2,7,8,13
+        v2 = u32_wrapping_add(u32_wrapping_add(v2, v7), *m_span.at(*sigma[12]));
+        v13 = rotr16(v13 ^ v2);
+        v8 = u32_wrapping_add(v8, v13);
+        v7 = rotr12(v7 ^ v8);
+        v2 = u32_wrapping_add(u32_wrapping_add(v2, v7), *m_span.at(*sigma[13]));
+        v13 = rotr8(v13 ^ v2);
+        v8 = u32_wrapping_add(v8, v13);
+        v7 = rotr7(v7 ^ v8);
+
+        // 7 - 3,4,9,14
+        v3 = u32_wrapping_add(u32_wrapping_add(v3, v4), *m_span.at(*sigma[14]));
+        v14 = rotr16(v14 ^ v3);
+        v9 = u32_wrapping_add(v9, v14);
+        v4 = rotr12(v4 ^ v9);
+        v3 = u32_wrapping_add(u32_wrapping_add(v3, v4), *m_span.at(*sigma[15]));
+        v14 = rotr8(v14 ^ v3);
+        v9 = u32_wrapping_add(v9, v14);
+        v4 = rotr7(v4 ^ v9);
 
         // ROUND function end
 
diff --git a/src/common/tests/test_array_append.cairo b/src/common/tests/test_array_append.cairo
index 6ef8961c5..cadd8f2cd 100644
--- a/src/common/tests/test_array_append.cairo
+++ b/src/common/tests/test_array_append.cairo
@@ -51,3 +51,43 @@ fn test_array_append_le_4() {
     assert((*result[6]) == 0x89ac0246, 'Invalid value');
     assert((*result[7]) == 0x2866b5eb, 'Invalid value');
 }
+
+#[test]
+#[available_gas(9999999999)]
+fn test_array_append_le_5() {
+    let value: Array<felt252> = array![1, 2, 3, 4];
+    let mut result = ArrayTrait::<u32>::new();
+    result.append_little_endian(value.span());
+    assert((*result[0]) == 0x1, 'Invalid value');
+    assert((*result[1]) == 0x0, 'Invalid value');
+    assert((*result[2]) == 0x0, 'Invalid value');
+    assert((*result[3]) == 0x0, 'Invalid value');
+    assert((*result[4]) == 0x0, 'Invalid value');
+    assert((*result[5]) == 0x0, 'Invalid value');
+    assert((*result[6]) == 0x0, 'Invalid value');
+    assert((*result[7]) == 0x0, 'Invalid value');
+    assert((*result[8]) == 0x2, 'Invalid value');
+    assert((*result[9]) == 0x0, 'Invalid value');
+    assert((*result[10]) == 0x0, 'Invalid value');
+    assert((*result[11]) == 0x0, 'Invalid value');
+    assert((*result[12]) == 0x0, 'Invalid value');
+    assert((*result[13]) == 0x0, 'Invalid value');
+    assert((*result[14]) == 0x0, 'Invalid value');
+    assert((*result[15]) == 0x0, 'Invalid value');
+    assert((*result[16]) == 0x3, 'Invalid value');
+    assert((*result[17]) == 0x0, 'Invalid value');
+    assert((*result[18]) == 0x0, 'Invalid value');
+    assert((*result[19]) == 0x0, 'Invalid value');
+    assert((*result[20]) == 0x0, 'Invalid value');
+    assert((*result[21]) == 0x0, 'Invalid value');
+    assert((*result[22]) == 0x0, 'Invalid value');
+    assert((*result[23]) == 0x0, 'Invalid value');
+    assert((*result[24]) == 0x4, 'Invalid value');
+    assert((*result[25]) == 0x0, 'Invalid value');
+    assert((*result[26]) == 0x0, 'Invalid value');
+    assert((*result[27]) == 0x0, 'Invalid value');
+    assert((*result[28]) == 0x0, 'Invalid value');
+    assert((*result[29]) == 0x0, 'Invalid value');
+    assert((*result[30]) == 0x0, 'Invalid value');
+    assert((*result[31]) == 0x0, 'Invalid value');
+}