[UVa] 136 Ugly Number.cpp

#include <cstdio>
#include <algorithm>
using namespace std;
int main()
{
    unsigned long long int N[1501];
    N[1]=1;
    int p2=1,p3=1,p5=1;
    for (int n=2; n<=1500; n++){
        while (N[p2]*2 <= N[n-1]) p2++;
        while (N[p3]*3 <= N[n-1]) p3++;
        while (N[p5]*5 <= N[n-1]) p5++;
        N[n] = min (N[p2]*2, min (N[p3]*3, N[p5]*5));
    }
    printf("The 1500'th ugly number is %llu.\n",N[1500]);
}