View Compilation Error

0_0_16822067_17254.cpp: In function 'int main()':
0_0_16822067_17254.cpp:12:18: error: 'scanf' was not declared in this scope
     scanf("%d",&t);
                  ^
0_0_16822067_17254.cpp:26:42: error: 'printf' was not declared in this scope
         if(su)printf("%d %d\n",b,prime[i]);
                                          ^
0_0_16822067_17254.cpp:27:29: error: 'printf' was not declared in this scope
         else printf("FALL\n");
                             ^