263.Ugly Number

/* Write a program to check whether a given number is an ugly number.Ugly numbers are positive numbers whose prime factors only include 2, 3, 5. For example, 6, 8 are ugly while 14 is not ugly since it includes another prime factor 7.Note that 1 is typically treated as an ugly number. *///解法一 6msint fun(int num){    if(num%2==0)        num=num/2;    else if(num%3==0)        num=num/3;    else if(num%5==0)        num=num/5;    if(num%2==0||num%3==0||num%5==0)       num = fun(num);        if(num==1)        return 1;    return 0;}bool isUgly(int num) {    int i;    int k;    if(num<=0)        return false;    if(num==1)        return true;    k=fun(num);    if(k==1)        return true;    else        return false;    return;}//解法二 3msbool isUgly(int num) {    int i;    for(i=2;i<6&&num;i++)        while(num%i==0)            num/=i;    if(num==1)        return true;    else        return false;}