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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.
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题意：判断一个数是不是丑数。只能被2,3,5因子的。
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public
class
Solution {
public
boolean
isUgly(
int
num) {
if
(num==
0
)
return
false
;
while
(num%
2
==
0
){
num=num/
2
;
}
while
(num%
3
==
0
){
num=num/
3
;
}
while
(num%
5
==
0
){
num=num/
5
;
}
return
num==
1
?
true
:
false
;
}
}
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PS:直接做除法就行。
本文转自 努力的C 51CTO博客，原文链接:http://blog.51cto.com/fulin0532/1905431
