学步园

思路：直接判断循环的数量num是否与mod相等

#include<stdio.h>
#include<string.h>

int vis[100005];

int main(){
	int step, mod, seed, num, flag;
	while (scanf("%d %d", &step, &mod) != EOF){
		num = seed = 0,flag = 1;	
		memset(vis, 0, sizeof(vis));	
		while (num < mod){
			seed = (seed + step) % mod;	
			num++;	
			if (!vis[seed])	
				vis[seed] = 1;	
			else{
				flag = 0;	
				break;	
			}	
		}	
		if (flag)
			printf("%10d%10d%15s\n", step, mod, "Good Choice");
		else
			printf("%10d%10d%14s\n", step, mod, "Bad Choice");
		printf("\n");	
	}
	return 0;
}