View Compilation Error

1_734_4846_6875.cpp: In function 'int main()':
1_734_4846_6875.cpp:4:18: error: 'scanf' was not declared in this scope
     scanf("%d",&t);  
                  ^
1_734_4846_6875.cpp:7:23: error: 'n' was not declared in this scope
         scanf("%d%d",&n,&m);  
                       ^
1_734_4846_6875.cpp:7:26: error: 'm' was not declared in this scope
         scanf("%d%d",&n,&m);  
                          ^
1_734_4846_6875.cpp:8:31: error: 'printf' was not declared in this scope
         printf("Case #%d: ",t1);  
                               ^