最大公约数
Description
There is a hill with n holes around. The holes are signed from 0 to n-1.
A rabbit must hide in one of the holes. A wolf searches the rabbit in anticlockwise order. The first hole he get into is the one signed with 0. Then he will get into the hole every m holes. For example, m=2 and n=6, the wolf will get into the holes which are signed 0,2,4,0. If the rabbit hides in the hole which signed 1,3 or 5, she will survive. So we call these holes the safe holes.
Input
The input starts with a positive integer P which indicates the number of test cases. Then on the following P lines,each line consists 2 positive integer m and n(0<m,n<2147483648).
Output
For each input m n, if safe holes exist, you should output "YES", else output "NO" in a single line.
Sample Input
2
1 2
2 2
Sample Output
NO
YES
题目大意:狼钻入洞中寻找兔子,第一次从编号为0的洞口进入,再从第m个洞口进入,问狼能否吃到兔子,如果可以输出“YES”,否则输出“NO”.
分析:此题为最大公约数,如果gcd(m,n)==1,则狼就能吃到兔子。
代码如下:
#include <iostream> #include <cstdio> using namespace std; unsigned int gcd(unsigned int a,unsigned int b) { return b==0? a:gcd(b,a%b); } int main() { int t; unsigned int m,n; scanf("%d",&t); while(t--) { scanf("%u%u",&m,&n); if(gcd(m,n)==1) printf("NO\n"); else printf("YES\n"); } return 0; }