茹靖涵 level 1 已完成

p01/p01.cpp

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+#include <iostream>
+#include <windows.h>
+#include <stdlib.h>
+using namespace std;
+int main() {
+    HANDLE hOut;
+    CONSOLE_SCREEN_BUFFER_INFO a;
+    hOut = GetStdHandle(STD_OUTPUT_HANDLE);
+    GetConsoleScreenBufferInfo(hOut, &a);
+    int length_of_console = a.dwSize.X;
+    int flag = 0; // symbolize whether 'a' has reached the two sides
+    while(1){
+        for(int i=0;i<length_of_console;i++){
+            for (int j=0;j<i;j++)cout << " ";
+            cout << "A";
+            Sleep(30);
+            if (i == length_of_console - 1) flag = 1; // so that 'a' could turn left
+            if (i == 0)  flag = 0;
+            if (flag) i -= 2;
+            system("cls");
+        }
+    }
+    system("pause");
+    return 0;
+}
+

p02/p02.cpp

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+#include <iostream>
+#include<cstdio>
+using namespace std;
+bool isPrime(int x){ // simple version
+    if (x == 1) return false;
+    for(int i = 2; i * i <= x; i++) if (x % i == 0) return false;
+    return true;
+}
+int main() {
+    int n;
+    cin >> n;
+    bool ans = isPrime(n);
+    if (ans) printf("%d is a prime.\n",n);
+    else printf("%d is not a prime.\n",n);
+    system("pause");
+    return 0;
+}

p03_1/p03-1.cpp

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+#include <iostream>
+using namespace std;
+const int lifetime = 84; // His lifetime could be divided by 12 and 7,so by common sense,his lifetime is 84.
+const int childhood = 14;
+const int youth = 7;
+const int bachelor = 12;
+const int marriage = 5;
+int main() {
+    int father = childhood + youth + bachelor + marriage;
+    int son = 0;
+    int time = lifetime - 4 - father;
+    if (time == lifetime / 2) cout << 80 << endl;
+    return 0;
+}

p03_2/p03-2.cpp

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+#include <iostream>
+using namespace std;
+const int max_lifetime = 800; // the life span of the legendary "PengZu"
+int main() {
+    for(int i=0;i<max_lifetime;i++){ // i is the lifetime of Diophantus
+        if(i % 6 != 0 || i % 12 != 0 || i%7 != 0)  continue;
+        int childhood = i / 6;
+        int youth = i / 12;
+        int bachelor = i / 7;
+        int marriage = 5;
+        int father = childhood + youth + bachelor + marriage;
+        int son = 0;
+        for(int j = 1;j <= i-father;j++){
+            if(son == i/2 && father + son + 4 == i) {
+                cout << i << endl;
+                break;
+            } else son++;
+        }
+    }
+    system("pause");
+    return 0;
+}

p04/p04.cpp

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+#include <iostream>
+using namespace std;
+int digit[5]; // record every digit of the number
+int main() {
+    for(int i = 100;i < 1000;i++){
+        int tmp = i;
+        for(int j = 1;j <= 3;j++){
+            digit[j] = tmp % 10;
+            tmp /= 10;
+        }
+        int i0 = digit[1] * digit[1] * digit[1];
+        int i1 = digit[2] * digit[2] * digit[2];
+        int i2 = digit[3] * digit[3] * digit[3];
+        if(i == i0 + i1 + i2) cout << i << endl;
+    }
+    return 0;
+}

p05_1/p05_1.cpp

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+#include <iostream>
+#include <time.h>
+using namespace std;
+int isPrime(int n){ // ordinary algorithm
+    if(n == 1) return 0;
+    for (int i = 2;i * i <= n;i++){
+        if (n % i == 0) return 0;
+    }
+    return 1;
+}
+int main() {
+    int begintime,endtime;
+    begintime = clock();
+    for(int i = 2;i <= 1000;i++){
+        if(isPrime(i)) cout << i << ' ';
+    }
+    endtime = clock();
+    cout << "Runtime is " << endtime - begintime << "ms" << endl;
+    return 0;
+}

p05_2/p05_2.cpp

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+#include <stdio.h>
+#include <time.h>
+int main() {
+    int begintime,endtime;
+    begintime = clock();
+    printf("2 3 5 7 11 13 17 19 23 29 31 37 41 43 47 53 59 61 67 71 73 79 83 89 97 101 103 107 109 113 127 131 137 139 149 151 157 1\n"
+           "63 167 173 179 181 191 193 197 199 211 223 227 229 233 239 241 251 257 263 269 271 277 281 283 293 307 311 313 317 331 3\n"
+           "37 347 349 353 359 367 373 379 383 389 397 401 409 419 421 431 433 439 443 449 457 461 463 467 479 487 491 499 503 509 5\n"
+           "21 523 541 547 557 563 569 571 577 587 593 599 601 607 613 617 619 631 641 643 647 653 659 661 673 677 683 691 701 709 7\n"
+           "19 727 733 739 743 751 757 761 769 773 787 797 809 811 821 823 827 829 839 853 857 859 863 877 881 883 887 907 911 919 9\n"
+           "29 937 941 947 953 967 971 977 983 991 997"); // Apparently this is the most efficient algorithm
+    endtime = clock();
+    printf("Runtime is %dms",endtime - begintime);
+    return 0;
+}

p05_3/p05_3.cpp

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+#include <iostream>
+#include <string.h>
+#include <time.h>
+using namespace std;
+int main() { // Use"ShaiFa"
+    int begintime,endtime;
+    begintime = clock();
+    int f[1005]; // identify whether the number is a prime
+    memset(f,1,sizeof f);
+    for(int i = 2;i < 1000;i++){
+        if(f[i])
+            for(int j = 2; j * i <= 1000; j++) f[i*j] = 0;
+    }
+    for(int i = 2;i < 1000;i++) if (f[i]) cout << i << ' ';
+    endtime = clock();
+    cout << "Runtime is " << endtime - begintime << "ms" << endl;
+    return 0;
+}

p06/p06.cpp

@@ -0,0 +1,26 @@
+#include <iostream>
+#include <stdio.h>
+using namespace std;
+int isPrime(int x){
+    for (int i = 2; i * i <= x; i++){
+        if (x % i == 0) return 0;
+    }
+    return 1;
+}
+int main() {
+    int prime[30];
+    int cnt = 0;
+    for (int n = 2; n < 100; n++){
+        if(isPrime(n)) prime[++cnt] = n;
+    }
+    for(int x = 4 ; x <= 100; x += 2){
+        for(int i = 1; i <= cnt; i++){
+            if (isPrime(x - prime[i])){ // could use binary search in prime[] to optimize
+                printf("%d = %d + %d\n",x,prime[i],x-prime[i]);
+                break;
+            }
+        }
+    }
+    system("pause");
+    return 0;
+}

p07/p07.cpp

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+#include <iostream>
+#include <string>
+using namespace std;
+string a;
+char b[1000005];
+void encrypt(string s) {
+    for (int i = 0; i < s.length(); i++){
+        b[i] = s[i] + 3;
+        cout << b[i];
+    }
+    cout << endl;
+}
+void decrept(){
+    for (int i = 0; i < a.length(); i++){
+        char tmp = b[i] - 3;
+        cout << tmp;
+    }
+    cout << endl;
+}
+int main() {
+    cin >> a;
+    encrypt(a);
+    decrept();
+    system("pause");
+    return 0;
+}
+

p08/p08.cpp

@@ -0,0 +1,73 @@
+#include <iostream>
+#include <cstdio>
+#include <stack>
+using namespace std;
+int n;
+stack<int> a,b,c;
+
+void output(int n, int x, char a, char b){
+    printf("%d : %d from %c to %c\n",n,x,a,b);
+}
+
+char get_top(char x){
+    int tmp;
+    if(x == 'a'){
+        tmp = a.top();
+    } else if(x == 'b'){
+        tmp = b.top();
+    } else{
+        tmp = c.top();
+    }
+    return tmp;
+}
+
+void reverse(char x, char y){
+    int tmp;
+    if(x == 'a' && y == 'b'){
+        tmp = a.top();
+        a.pop();
+        b.push(tmp);
+    }else if(x == 'a' && y == 'c'){
+        tmp = a.top();
+        a.pop();
+        c.push(tmp);
+    }else if(x == 'b' && y == 'a'){
+        tmp = b.top();
+        b.pop();
+        a.push(tmp);
+    }else if(x == 'b' && y == 'c'){
+        tmp = b.top();
+        b.pop();
+        c.push(tmp);
+    }else if(x == 'c' && y == 'a'){
+        tmp = c.top();
+        c.pop();
+        a.push(tmp);
+    }else if(x == 'c' && y == 'b'){
+        tmp = c.top();
+        c.pop();
+        b.push(tmp);
+    }
+}
+
+void solve(int n, char x, char y, char z){
+    if(n == 1){
+        output(n,get_top(x),x,z);
+        reverse(x,z);
+        return;
+    }
+    solve(n-1, x,z,y);
+    output(n,get_top(x),x,z);
+    reverse(x,z);
+    solve(n-1,y,x,z);
+}
+int main(){
+    char x = 'a',y = 'b',z = 'c';
+    cin >> n;
+    for(int i = n; i >= 1; i --){
+        a.push(i);
+    }
+    solve(n,x,y,z);//
+    system("pause");
+    return 0;
+}