/in/foo.c: In function 'main':
/in/foo.c:4:26: error: 'cin' undeclared (first use in this function)
     for(int i=0;i<10;i++)cin >> height[i];
                          ^~~
/in/foo.c:4:26: note: each undeclared identifier is reported only once for each function it appears in
/in/foo.c:4:33: error: 'height' undeclared (first use in this function)
     for(int i=0;i<10;i++)cin >> height[i];
                                 ^~~~~~
/in/foo.c:5:12: error: 'H' undeclared (first use in this function)
     cin >> H;
            ^
/in/foo.c:7:26: error: 's' undeclared (first use in this function)
     for(int i=0;i<10;i++)s+=!(H<height[i]);
                          ^
/in/foo.c:8:5: error: 'cout' undeclared (first use in this function)
     cout << s;
     ^~~~