#include<iostream>
#include<cstdio>
#include<bits/stdc++.h>
using namespace std;
string s;
int a,b,i,len;
int main(){
	cin>>s;
	len=s.length();
	for(i=0;i<=len;i++){
		if(s[i]>=65&&s[i]<=90){
			a++;
		}else if(s[i]>=97&&s[i]<=122){
			b++;
		}
	}
	if(a>b){
		for(i=0;i<=len;i++){
			if(s[i]>=97&&s[i]<=122){
				s[i]-=32;
			}
		}
	}else{
		for(i=0;i<=len;i++){
			if(s[i]>=65&&s[i]<=90){
				s[i]+=32;
			}
		}
	}
	cout<<s;
	return 0;
}

总之样例过了...