遍历一遍，遇到边界为奇数次时，格子在多边形内

偶数次时，在多边形外

#include
    
     #define REP(i, a, b) for(int i = (a); i < (b); i++)using namespace std;int main(){	char s[105];	int n, m;	while(~scanf("%d%d", &n, &m))	{		int ans = 0, c = 0;		REP(i, 0, n)		{			int in = 0;			scanf("%s", s);			REP(j, 0, m)			{				if(s[j] == '/' || s[j] == '\\') c++, in = !in;				else if(in) ans++;			}		}		printf("%d\n", ans + c / 2);	}	return 0;}