View Compilation Error

0_0_19216170_28533.cpp: In function 'int main()':
0_0_19216170_28533.cpp:54:15: error: 'scanf' was not declared in this scope
  scanf("%d",&T);
               ^
0_0_19216170_28533.cpp:57:23: error: 'printf' was not declared in this scope
   if(flag) printf("\n");
                       ^
0_0_19216170_28533.cpp:66:56: error: 'printf' was not declared in this scope
   if(JUDGE()) {printf("Could not complete this grid.\n");continue;}
                                                        ^
0_0_19216170_28533.cpp:74:43: error: 'printf' was not declared in this scope
     for(l=0;l<9;l++) printf("%d",ans[i][l]);
                                           ^
0_0_19216170_28533.cpp:75:16: error: 'printf' was not declared in this scope
     printf("\n");
                ^
0_0_19216170_28533.cpp:78:48: error: 'printf' was not declared in this scope
   else printf("Could not complete this grid.\n");
                                                ^