find the Ugly Number

import java.util.*;
import java.lang.*;
public class Solution {
    public int GetUglyNumber_Solution(int index) {
        if(index<7)return index;
        int[] dp=new int[index+1];
        dp[1]=1;
        int mid2=1,mid3=1,mid5=1,i;
        for(i=2;i<index+1;i++){
            dp[i]=Math.min(dp[mid2]*2,Math.min(dp[mid3]*3,dp[mid5]*5));
            if(dp[mid2]*2==dp[i]) mid2++;
            if(dp[mid3]*3==dp[i]) mid3++;
            if(dp[mid5]*5==dp[i]) mid5++;
        }
        return dp[index];
        }
    
        
    }