ZOJ-2795

#include<stdio.h>int main(){    int n;    int array[100000];    while (scanf("%d", &n), n)    {        int i, flag = 1;        for (i = 0; i < n; i++)            scanf("%d", &array[i]);        for (i = 0; i < n; i++)            if (i + 1 != array[array[i] - 1])            {                flag = 0;                break;            }        printf(flag ? "ambiguous\n" : "not ambiguous\n");    }    return 0;}