View Compilation Error

0_0_34533227_21860.cpp: In function 'int main()':
0_0_34533227_21860.cpp:9:26: error: 'scanf' was not declared in this scope
  while(scanf("%d%d",&x,&y)!=EOF){
                          ^
0_0_34533227_21860.cpp:9:29: error: 'EOF' was not declared in this scope
  while(scanf("%d%d",&x,&y)!=EOF){
                             ^
0_0_34533227_21860.cpp:14:24: error: 's' was not declared in this scope
   qsort(sum,x+y,sizeof(s[0]),cmp);
                        ^
0_0_34533227_21860.cpp:17:36: error: 'printf' was not declared in this scope
                 printf("%d", sum[i]);
                                    ^
0_0_34533227_21860.cpp:22:41: error: 'printf' was not declared in this scope
                     printf(" %d", sum[i]);
                                         ^
0_0_34533227_21860.cpp:25:20: error: 'printf' was not declared in this scope
         printf("\n");
                    ^