View Compilation Error

0_0_32864524_31762.cpp: In function 'int main()':
0_0_32864524_31762.cpp:33:24: error: 'scanf' was not declared in this scope
     int T;scanf("%d",&T);
                        ^
0_0_32864524_31762.cpp:37:19: error: 'strlen' was not declared in this scope
         n=strlen(x);
                   ^
0_0_32864524_31762.cpp:40:29: error: 'printf' was not declared in this scope
         printf("%d\n",KMP() );
                             ^