欧几里得算法(辗转相除法)

public class  {

    
    public int Gcd(int m, int n){
        if(m==0) return n;
        if(n==0) return m;
        if(m>n){int tmp=m; m=n; n=tmp;}
        while(m>0){
            int c=n%m;
            n=m;
            m=c;
        }
        return n;
    }
}