View Compilation Error

0_0_19531522_455.cpp: In function 'int main()':
0_0_19531522_455.cpp:23:29: error: 'scanf' was not declared in this scope
  while (scanf("%d%d", &n, &V) != EOF) {
                             ^
0_0_19531522_455.cpp:23:34: error: 'EOF' was not declared in this scope
  while (scanf("%d%d", &n, &V) != EOF) {
                                  ^
0_0_19531522_455.cpp:30:24: error: 'sort' was not declared in this scope
   sort(f + 1, f + 1 + m);   
                        ^
0_0_19531522_455.cpp:35:35: error: 'printf' was not declared in this scope
   if (ss<V) { printf("%I64d\n", ss); continue; } 
                                   ^
0_0_19531522_455.cpp:39:33: error: 'memset' was not declared in this scope
   memset(hash2, 0, sizeof(hash2));
                                 ^
0_0_19531522_455.cpp:43:21: error: 'printf' was not declared in this scope
   printf("%d\n", Max);
                     ^