POJ 1338 - Ugly Numbers



Time Limit: 1000MS Memory Limit: 10000KTotal Submissions: 19864 Accepted: 8813

Description

Ugly numbers are numbers whose only prime factors are 2, 3 or 5. The sequence
1, 2, 3, 4, 5, 6, 8, 9, 10, 12, ...
shows the first 10 ugly numbers. By convention, 1 is included.
Given the integer n,write a program to find and print the n'th ugly number.

Input

Each line of the input contains a postisive integer n (n <= 1500).Input is terminated by a line with n=0.

Output

For each line, output the n’th ugly number .:Don’t deal with the line with n=0.

Sample Input

1290

Sample Output

1210

Source

New Zealand 1990 Division I,UVA 136

#include <iostream>using namespace std;int a[1505];int main(){int i,j,k;int aa=1,b=1,c=1;a[1]=1;for(i=2;i<=1500;i++){a[i]=min(a[aa]*2,min(a[b]*3,a[c]*5));if(a[i]==a[aa]*2)aa++;if(a[i]==a[b]*3)b++;if(a[i]==a[c]*5)c++;}while(1){cin>>i;if(i==0)return 0;cout<<a[i]<<endl;}return 0;}