View Compilation Error

0_0_25830805_17590.cpp: In function 'int main(int, char**)':
0_0_25830805_17590.cpp:19:21: error: 'scanf' was not declared in this scope
  while(scanf("%d",&N) != EOF){
                     ^
0_0_25830805_17590.cpp:19:26: error: 'EOF' was not declared in this scope
  while(scanf("%d",&N) != EOF){
                          ^
0_0_25830805_17590.cpp:22:17: error: 'printf' was not declared in this scope
    printf("-1\n");
                 ^
0_0_25830805_17590.cpp:36:20: error: 'printf' was not declared in this scope
   printf("%ld\n",mm);
                    ^