【floyd】 ASC 28 J. Triatrip

算是floyd的变形吧。。。用bitset优化～

#include <iostream>
#include <queue>
#include <stack>
#include <map>
#include <set>
#include <bitset>
#include <cstdio>
#include <algorithm>
#include <cstring>
#include <climits>
#include <cstdlib>
#include <cmath>
#include <time.h>
#define maxn 1505
#define maxm 500005
#define eps 1e-12
#define mod 998244353
#define INF 0x3f3f3f3f
#define PI (acos(-1.0))
#define lowbit(x) (x&(-x))
#define mp make_pair
//#define ls o<<1
//#define rs o<<1 | 1
//#define lson o<<1, L, mid 
//#define rson o<<1 | 1, mid+1, R
//#pragma comment(linker, "/STACK:102400000,102400000")
#define pii pair<int, int> 
typedef long long LL;
typedef unsigned long long ULL;
//typedef int LL;
using namespace std;
LL qpow(LL a, LL b){LL res=1,base=a;while(b){if(b%2)res=res*base;base=base*base;b/=2;}return res;}
LL powmod(LL a, LL b){LL res=1,base=a;while(b){if(b%2)res=res*base%mod;base=base*base%mod;b/=2;}return res;}
// head

char g[maxn][maxn];
bitset<maxn> bs1[maxn], bs2[maxn], res;
int n;

LL floyd()
{
	LL ans = 0;
	for(int i = 1; i <= n; i++)
		for(int j = 1; j <= n; j++) {
			if(bs1[i][j] == 0) continue;
			res = bs1[j] & bs2[i];
			ans += res.count();
		}
	return ans / 3;
}
void work()
{
	for(int i = 1; i <= n; i++) scanf("%s", g[i]+1);
	
	for(int i = 1; i <= n; i++) bs1[i].reset(), bs2[i].reset();

	for(int i = 1; i <= n; i++)
		for(int j = 1; j <= n; j++)
			if(g[i][j] == '+')
				bs1[i][j] = 1, bs2[j][i] = 1;
	LL ans = floyd();
	printf("%I64d\n", ans);
}

int main()
{
	freopen("triatrip.in", "r", stdin);
	freopen("triatrip.out", "w", stdout);
	while(scanf("%d", &n)!=EOF) {
		work();
	}
	
	return 0;
}