Andrei negura homework2

src/Homework1/ex10_BooleanStringContainsAnotherString.java

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+package Homework1;
+
+public class ex10_BooleanStringContainsAnotherString {
+    public static void main(String[] args) {
+        String s1 = "Hello java world";
+        String s2 = "java";
+
+        if(s1.contains(s2)){
+            System.out.println("TRUE");
+}else
+        System.out.println("FALSE");
+        }
+}
+
+/*
+Write a program that test if a given String contains another String.
+
+For example
+Given the following base String “Hello java world” and the target test String “java” the output should be TRUE
+ */

src/Homework1/ex11_CountCharacterInAString.java

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+package Homework1;
+
+public class ex11_CountCharacterInAString {
+    public static void main(String[] args) {
+        String s = "Hello java world";
+        char target = 'l';
+        int count = 0;
+
+        for (int i = 0; i < s.length(); i++) {
+            if (s.charAt(i) == target) {
+                count++;
+            }
+        }
+        System.out.println(count);
+    }
+}
+/*
+Write a program that will count how many times a character appears in a String
+For example
+Given the string “Hello java world” and the target character ‘a’ the output should be 2
+(since ‘a’ appears twice in “Hello java world”)
+ */

src/Homework1/ex12_BooleanStringEndsWithString.java

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+package Homework1;
+
+import static java.lang.Boolean.FALSE;
+import static java.lang.Boolean.TRUE;
+
+public class ex12_BooleanStringEndsWithString {
+    public static void main(String[] args) {
+        String sir1 = "Hello java world";
+        String sir2 = "world";
+
+        System.out.println("Sirul " + sir1 + " se termina cu " + sir2 + " : " + isSufix(sir1, sir2));
+    }
+    private static boolean isSufix(String sir1, String sir2) {
+        String[] words = sir1.split(" ");
+
+        if (words[words.length - 1].equals(sir2))
+            return true;
+        else
+            return false;
+    }
+}
+    /* Write a program that will test whether a string ends with another string
+
+        For example
+        Given the following strings “Hello java world” and “world” the output should be TRUE
+
+        */

src/Homework1/ex13_ReturnDifferentString.java

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+package Homework1;
+
+import java.util.HashMap;
+import java.util.Map;
+
+public class ex13_ReturnDifferentString {
+    public static void main(String[] args) {
+        String alphabet = "abcdefgh";
+        System.out.println(parse(alphabet));
+    }
+    // ex11_CountCharacterInAString letter = alphabet(0);
+    //  System.out.println(result);
+    public static String parse(String alphabet) {
+        Map<String, Integer> map = new HashMap<String, Integer>();
+        //Adding elements to map
+        map.put("a", 0);
+        map.put("b", 1);
+        map.put("c", 2);
+        map.put("d", 3);
+        map.put("e", 4);
+        map.put("f", 5);
+        map.put("g", 6);
+        map.put("h", 7);
+        map.put("i", 8);
+        map.put("j", 9);
+        map.put("k", 10);
+        map.put("l", 11);
+        map.put("m", 12);
+        map.put("n", 13);
+        map.put("o", 14);
+        map.put("p", 15);
+        map.put("q", 16);
+        map.put("r", 17);
+        map.put("s", 18);
+        map.put("t", 19);
+        map.put("u", 20);
+        map.put("v", 21);
+        map.put("w", 22);
+        map.put("x", 23);
+        map.put("y", 24);
+        map.put("z", 25);
+        String z = ""+ map.get("z");
+        String result = "";
+//    Set<String> keys = map.keySet();
+//    for (String k : keys) {
+//        System.out.println("Key: " + k)
+        for (int i = 0; i < alphabet.length(); i++) {
+            result += map.get(""+alphabet.charAt(i));
+        }
+        return result;
+    }
+}
+/*
+Write a program that will return a different string representing the alphabet index of each letter.
+Assuming we have the following alphabet encoding
+a = 0
+b = 1
+c = 2
+d = 3
+…
+For the given string “abcd” the output should be “0123”
+ */
+
+

src/Homework1/ex14_InsertSymbolsBetweenDuplicates.java

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+package Homework1;
+public class ex14_InsertSymbolsBetweenDuplicates {
+    public static void main(String[] args) {
+        String lett = "Hello worlld this is someething cooll";
+        String lett2 = "Hellllllo";
+        String insert = "-";
+        System.out.println(processString(lett,insert));
+        System.out.println(processString(lett2,"$"));
+    }
+    private static String processString(String s, String delimitator) {
+        StringBuilder rs = new StringBuilder();
+        if (s.length() > 1)
+            for (int i = 0; i < s.length() - 1; i++) {
+                if (s.charAt(i) == s.charAt(i + 1)) {
+                    rs.append( s.substring(i, i + 1)).append(delimitator);
+                } else {
+                    rs.append( s.substring(i, i + 1));
+                }
+            }
+        rs.append(s.substring(s.length() - 1));
+        return rs.toString();
+    }
+}
+
+/*
+Write a program that will insert a # between any duplicate letters that are placed right next to each.
+For example
+
+Given the following string “Hello world” the output should be “Hel#lo world”
+ */

src/Homework1/ex15_Palindrom.java

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+package Homework1;
+
+public class ex15_Palindrom {
+    public static void main(String[] args) {
+        String s1 = "ababa";
+        String s2 = "aba";
+        String s3 = "abba";
+        String s4 = "aaaabaaaa";
+        String s5 = "abbabb";
+        System.out.println("The provided string" + s1 + " is palindrome: " + isPalindrome(s1));
+        System.out.println("The provided string" + s2 + " is palindrome: " + isPalindrome(s2));
+        System.out.println("The provided string" + s3 + " is palindrome: " + isPalindrome(s3));
+        System.out.println("The provided string" + s4 + " is palindrome: " + isPalindrome(s4));
+        System.out.println("The provided string" + s5 + " is palindrome: " + isPalindrome(s5));
+    }
+
+    private static boolean isPalindrome(String s) {
+//        StringBuilder reversedString = new StringBuilder(s).reverse();
+//        return s.equals(reversedString.toString());
+        boolean isPalindrome = true;
+        int n = s.length() / 2;
+        int lenght = s.length() - 1;
+        for (int i = 0; i <= n; i++) {
+            if (s.charAt(i) != s.charAt(lenght - i)) {
+                isPalindrome = false;
+                break;
+            }
+        }
+        return isPalindrome;
+    }
+}
+
+/*
+Write a program to test whether a given string is a palindrome or not
+
+For example
+Given the following string “aaabccbaaa” should return TRUE
+Given the following string “abccbb” should return FALSE
+ */

src/Homework1/ex1_Sum.java

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+package Homework1;
+
+    public class ex1_Sum {
+    public static void main(String[] args) {
+        int[] ints = {1, 2, 3, 4, 5, 6, 7, 8};
+// Calculate sum up all numbers from 0 up to a target number
+// Target number is 6
+    /*
+    int sum = ints[0] + ints[1] + ints[3] + ints[4] + ints[5];
+        System.out.println("suma numerelor alese din intervalul mentionat este: " + sum);
+     */
+
+        int sum = 0;
+        for (int i = 0; i < 6; i++) {
+            sum = sum + ints[i];
+        }
+        System.out.println("suma numerelor alese din intervalul mentionat este: " + sum);
+    }
+}
+
+/* Cerinta:
+Write a program that will sum up all numbers from 0 up to a target number.
+For example, for an input number 5, result should be 15 (0+1+2+3+4+5) */
+

src/Homework1/ex2_AverageAndSum.java

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+package Homework1;
+
+public class ex2_AverageAndSum {
+    public static void main(String[] args) {
+
+        int a = 1;
+        int b = 100;
+        int sum = 0;
+
+        for (int i = a; i <= b; i++) {
+            sum = sum + i;
+        }
+        System.out.println("suma valorilor din intervalul " + a + " si " + b + " este: " + sum);
+
+        double avg = (a + b) / 2;
+
+        System.out.println("media este:" + avg);
+    }
+}
+
+/*
+Cerinta:
+Write a program that will calculate the average and sum of all numbers between the range of 2 numbers.
+For example, for range numbers 1 to 100 output should be:
+Sum for range 1 to 100 : 5050
+Average for range 1 to 100 : 50.0
+*/
+