[Leetcode 263 264] Ugly number I II

Write a program to check whether a given number was an ugly number.

Ugly numbers is positive numbers whose prime factors only include2, 3, 5. For example,6, 8Is ugly while14is not ugly since it includes another prime factor7.

Note that's 1 typically treated as an ugly number.

Credits:

Special thanks to @jianchao. Li.fighter for adding the problem and creating all test cases.

AC Code:

Class Solution {public:    bool isugly (int num) {        if (num==0)            return false;        while (num!=1)        {            if (num%2==0)                NUM=NUM/2;            else if (num%3==0)                NUM=NUM/3;            else if (num%5==0)                NUM=NUM/5;            else break                ;        }        return num==1;}    ;

write a program to find The n -th ugly number.

ugly numbers is positive numbers whose prime factors only Include 2, 3, 5 . For Example, 1, 2, 3, 4, 5, 6, 8, 9, ten,  is the sequence of the First 10  ugly numbers.

Note that's 1 typically treated as an ugly number.

Of course it is possible to use the judgment function of I for a number and a number, but the time efficiency is not high.

AC Code:

Class Solution{public:    int minnum (int x,int y)    {        return x<y?x:y;    }    int nthuglynumber (int n)    {        if (n==0)            return 0;        int *count=new Int[n];        Count[0]=1;        int two=0;        int three=0;        int five=0;        int sum=1;        int min=0;        while (Sum<n)        {            min=minnum (Minnum (count[two]*2,count[three]*3), count[five]*5);            if (Min>count[sum-1])            {                count[sum]=min;                ++sum;            }            if (min==count[two]*2)                ++two;            else if (min==count[three]*3)                ++three;            else                ++five;        }        return count[sum-1];}    ;

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[Leetcode 263 264] Ugly number I II