HDU 3974 Assign the task

#include<stdio.h>
#define N 50010
int f[N], vis[N], task[N], n; //f数组保存父节点，即上司
void Init()
{
    int i;
    for (i = 0; i <= n; i++)
    {
        f[i] = i;
        vis[i] = 0;
        task[i] = -1;
    }
}
int Find(int x)
{
    int r = x, v = vis[x], ans = task[x]; //v是任务序号，ans是任务
    while (f[r] != r)
    {
        if (v < vis[f[r]]) //如果找到更靠后的序号，那就更新任务，及其序号
        {
            ans = task[f[r]];
            v = vis[f[r]];
        }
        r = f[r]; //不要忘啦一直查找其父节点，直自其根节点是本身
    }
    return ans;
}
int main ()
{
    int T, m, i, a, b, k = 0, num; //num记录的是分配任务的序号，那么当前任务一定是最后分配的
    char s[10];
    scanf("%d", &T);
    while (T--)
    {
        k++;
        num = 1;
        scanf("%d", &n);
        Init();
        for (i = 1; i < n; i++)
        {
            scanf("%d%d", &a, &b);
            f[a] = b;
        }
        scanf("%d", &m);
        printf("Case #%d:\n", k);
        while (m--)
        {
            scanf("%s", s);
            if (s[0] == ‘T‘)
            {
                scanf("%d%d", &a, &b);
                task[a] = b;
                vis[a] = num++; //每次分配任务，要记下序号
            }
            else if (s[0] == ‘C‘)
            {
                scanf("%d", &a);
                printf("%d\n", Find(a));
            }
        }
    }
    return 0;
}