ZOJ 3710 Friends

题目链接：ZOJ 3710 Friends

数据范围只有100，暴利可解，不过用vector超时了。

后来改成数组一直WA，队友改了下就过了，我没感觉出来两种写法的差异，诡异。

WA：

#include <iostream>
#include <cstring>
#include <cstdio>
#include <vector>
#include <algorithm>

using namespace std;

const int MAX_N = 100 + 10;
int vis[MAX_N][MAX_N];

int main()
{
    //freopen("in.txt", "r", stdin);
    int T;
    scanf("%d", &T);
    while(T--)
    {
        memset(vis, 0, sizeof(vis));
        int n, m, k, u, v, _max = 0;
        scanf("%d%d%d", &n, &m, &k);
        for(int i = 0; i < m; i++)
        {
            scanf("%d%d", &u, &v);
            vis[u][v] = vis[v][u] = 1;
            _max = max(_max, max(u, v));
        }
        int s1, s2, s3 = 0, s4 = 0;
        for(int i = 0; i <= _max; i++)
        {
            for(int j = i + 1; j <= _max; j++)
            {
                if(vis[i][j] == 1)
                    continue;
                s3 = 0;
                for(int p = 0; p <= _max; p++)
                {
                    if(vis[i][p] == vis[j][p] && vis[i][p] == 1)
                        s3++;
                }
                if(s3 >= k)
                {
                    vis[i][j] = vis[j][i] = 1;
                    s4++;
                    i = -1;
                    break;
                }
            }
        }
        printf("%d\n", s4);
    }
    return 0;
}

AC：

#include <iostream>
#include <cstring>
#include <cstdio>
#include <vector>
#include <algorithm>

using namespace std;

const int MAX_N = 100 + 10;
int vis[MAX_N][MAX_N];

int main()
{
    //freopen("in.txt", "r", stdin);
    int T;
    scanf("%d", &T);
    while(T--)
    {
        memset(vis, 0, sizeof(vis));
        int n, m, k, u, v, _max = 0;
        scanf("%d%d%d", &n, &m, &k);
        for(int i = 0; i < m; i++)
        {
            scanf("%d%d", &u, &v);
            vis[u][v] = vis[v][u] = 1;
           // _max = max(_max, max(u, v));
        }
        int s1, s2, s3 = 0, s4 = 0;
        for(int i = 0; i < n; i++)
        {
            for(int j = i + 1; j < n; j++)
            {
                if(vis[i][j] == 1)
                    continue;
                s3 = 0;
                for(int p = 0; p < n; p++)
                {
                    if(vis[i][p] == vis[j][p] && vis[i][p] == 1)
                        s3++;
                }
                if(s3 >= k)
                {
                    vis[i][j] = vis[j][i] = 1;
                    s4++;
                    i = -1;
                    break;
                }
            }
        }
        printf("%d\n", s4);
    }
    return 0;
}