# include <algorithm>
# include <stdio.h>
# include <string.h>
# include <math.h>
# include <iostream>
using namespace std;
int main()
{
    int n,m,i,a,b,cot;
    while(~scanf("%d%d",&n,&m))
    {
        cot=0;
        for(i=0; i<n; i++)
        {
            scanf("%d%d",&a,&b);
            cot^=abs(abs(a-b)-1);  // 把中间差的空格，即走的总步数，当作总石头数，
        }
        if(cot==0)//平衡状态，后手赢
            printf("BAD LUCK!\n");
        else
            printf("I WIN!\n");
    }
    return 0;
}

hdu 1730 Northcott Game (nim博弈变形)