foo.cpp:1:1: error: 'include' does not name a type
 include <bits/stdc++.h>
 ^~~~~~~
foo.cpp: In function 'int read()':
foo.cpp:7:29: error: 'getchar' was not declared in this scope
 int x=0,f=1;char ch=getchar();
                             ^
foo.cpp: In function 'int main()':
foo.cpp:15:22: error: 'scanf' was not declared in this scope
 while (scanf("%d", &n) == 1) {
                      ^
foo.cpp:27:40: error: 'max' was not declared in this scope
 ans = max(ans, (s[top] - pos[i]) * h[i]);
                                        ^
foo.cpp:30:19: error: 'printf' was not declared in this scope
 printf("%d\n", ans);
                   ^
foo.cpp:32:11: error: 'printf' was not declared in this scope
 printf("0");
           ^