View Compilation Error

0_0_19198236_10316.cpp: In function 'int main()':
0_0_19198236_10316.cpp:13:32: error: 'scanf' was not declared in this scope
     while(~scanf("%d%d", &a, &r))  
                                ^
0_0_19198236_10316.cpp:16:33: error: 'memset' was not declared in this scope
         memset(ma, 0, sizeof(ma));  
                                 ^
0_0_19198236_10316.cpp:26:25: error: 'printf' was not declared in this scope
             printf("0\n");  
                         ^
0_0_19198236_10316.cpp:30:27: error: 'printf' was not declared in this scope
                 printf("-");  
                           ^
0_0_19198236_10316.cpp:34:39: error: 'printf' was not declared in this scope
                     printf("%d", ma[i]);  
                                       ^
0_0_19198236_10316.cpp:36:50: error: 'printf' was not declared in this scope
                     printf("%c", ma[i] - 10 + 'A');  
                                                  ^
0_0_19198236_10316.cpp:39:24: error: 'printf' was not declared in this scope
             printf("\n");  
                        ^