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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