Ugly Numbers (POJ1338) (ugly number, strong skill)

Ugly Numbers

Time Limit: 1000MS		Memory Limit: 10000K
Total Submissions: 20851		Accepted: 9248

Description

Ugly numbers is numbers whose only prime factors is 2, 3 or 5. The sequence
1, 2, 3, 4, 5, 6, 8, 9, 10, 12, ...
Shows the first ten 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.:D On ' t deal with the line with N=0.

Sample Input

1290

Sample Output

1210

Source

New Zealand 1990 Division I,uva 136

#include <stdio.h> #include <algorithm>using namespace std;int min (int a,int b,int c) {return Min (A,min (b,c)) ;} int main () {int i,n,a[1505];int x=1,y=1,z=1;a[1]=1;for (i=2;i<=1500;i++) {a[i]=min (a[x]*2,a[y]*3,a[z]*5); if (a[i]= =A[X]*2) x + +;    if (a[i]==a[y]*3) y++;if (a[i]==a[z]*5) z++;} while (scanf ("%d", &n) &&n) {printf ("%d\n", A[n]);} return 0;}

Ugly Numbers (POJ1338) (ugly number, strong skill)