View Compilation Error

0_0_15293039_26403.cpp: In function 'int main()':
0_0_15293039_26403.cpp:18:28: error: 'memset' was not declared in this scope
  memset(sum, 0, sizeof(sum));
                            ^
0_0_15293039_26403.cpp:89:30: error: 'scanf' was not declared in this scope
  while (scanf("%d %d", &n, &m) != EOF)
                              ^
0_0_15293039_26403.cpp:89:35: error: 'EOF' was not declared in this scope
  while (scanf("%d %d", &n, &m) != EOF)
                                   ^
0_0_15293039_26403.cpp:94:27: error: 'printf' was not declared in this scope
   printf("%d\n", sum[n][m]);
                           ^