View Compilation Error

0_0_35183944_30402.cpp: In function 'int main()':
0_0_35183944_30402.cpp:29:16: error: 'scanf' was not declared in this scope
  scanf("%d", &t);
                ^
0_0_35183944_30402.cpp:30:17: error: 'clock' was not declared in this scope
  int tt = clock();
                 ^
0_0_35183944_30402.cpp:34:27: error: 'memset' was not declared in this scope
   memset(cl, 0, sizeof(cl));
                           ^
0_0_35183944_30402.cpp:60:23: error: 'printf' was not declared in this scope
    printf("Poor wyh\n");
                       ^
0_0_35183944_30402.cpp:63:30: error: 'printf' was not declared in this scope
    printf("%d %d\n", n - 1, 1);
                              ^
0_0_35183944_30402.cpp:66:23: error: 'printf' was not declared in this scope
    printf("Poor wyh\n");
                       ^
0_0_35183944_30402.cpp:70:16: error: 'swap' was not declared in this scope
     swap(s1, s2);
                ^
0_0_35183944_30402.cpp:72:28: error: 'printf' was not declared in this scope
    printf("%d %d\n", s1, s2);
                            ^