过山车

http://acm.hdu.edu.cn/showproblem.php?pid=2063 过山车

使用匈牙利算法求解

#include<stdio.h>
#include<string.h>
int adj_vex[501][501];
int match[501];
int flag[501];

int find(int v, int n)
{
    int i;
    for (i = 1; i <= n; i++)
    {
        if (adj_vex[v][i] == 1 && flag[i] == 0)
        {
            flag[i] = 1;
            if (match[i] == 0 || find(match[i], n) == 1)
            {
                match[i] = v;
                return 1;
            }
        }
    }
    return 0;
}

void main()
{
    int k, m, n;
    int i, j, male, female;
    int count;
//    freopen("input.txt", "r", stdin);
    while (scanf("%d", &k) != EOF && k != 0)
    {
        scanf("%d%d", &m, &n);
        for (i = 1; i <= m; i++)
        {
            for (j = 1; j <= n; j++)
            {
                adj_vex[i][j] = 0;
            }
        }

        for (i = 1; i <= k; i++)
        {
            scanf("%d%d", &male, &female);
            adj_vex[male][female] = 1;
        }
        count = 0;
        memset(match, 0, (n + 1)*sizeof(int));
        for (i = 1; i <= m; i++)
        {
            memset(flag, 0, (n + 1)*sizeof(int));
            if (find(i, n) == 1)
                count++;
        }
        printf("%d\n",count);
    }
}