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题目

代码

#include <bits/stdc++.h>
using namespace std;
const int R = 2e9+1; 
typedef long long LL;
unordered_set<LL> s;
int piles[5];
int dx[4] = {-1, 0, 1, 0}, dy[4] = {0, 1, 0, -1};
int dx1[4] = {-1, -1, 1, 1}, dy1[4] = {-1, 1, -1, 1};bool check(LL r)
{int y = r / R;int x = r % R;for(int i = 0; i < 4; i++){LL t = r + dx[i] + dy[i] * R;if(!s.count(t)) return false;}return true;
}int rate(LL r)
{int retval = 0;int y = r / R;int x = r % R;for(int i = 0; i < 4; i++){LL t = r + dx1[i] + dy1[i] * R;if(s.count(t)) retval++;}return retval;
}
int main()
{int n;cin >> n;for(int i = 1; i <= n; i++){int x, y;cin >> x >> y;x += 1e9; y += 1e9;LL r = 1ll * y * R + x;s.insert(r);}for(auto c : s){if(check(c)){piles[rate(c)]++;}}for(int i = 0; i < 5; i++){cout << piles[i] << "\n";}return 0;
}

爆int漏掉的可能地方

1. 函数返回值
2. 函数传参
3. 多项和
4. 乘积