C++ :

#include <bits/stdc++.h>
using namespace std;

int main(){
	int arr[1000],n,i,a = 0,b = 0,c = 0,d = 0;
	cin>>n;
	for(i = 0;i < n;i++){
		cin>>arr[i];
		if(arr[i] <= 18){
			a++;
		}else if(arr[i] <= 35){
			b++;
		}else if(arr[i] <= 60){
			c++;
		}else{
			d++;
		}
	}
	
	cout<<a<<" "<<fixed<<setprecision(2)<<a*100.0/n<<"%"<<endl;
	cout<<b<<" "<<fixed<<setprecision(2)<<b*100.0/n<<"%"<<endl;
	cout<<c<<" "<<fixed<<setprecision(2)<<c*100.0/n<<"%"<<endl;
	cout<<d<<" "<<fixed<<setprecision(2)<<d*100.0/n<<"%"<<endl;
	
}

Python :

n=int(input())
s1=list(map(int,input().split()))
alen=len([item for item in s1 if 0<=item<=18])
print("%d %.2lf%%"%(alen,100*alen/len(s1)))
alen=len([item for item in s1 if 19<=item<=35])
print("%d %.2lf%%"%(alen,100*alen/len(s1)))
alen=len([item for item in s1 if 36<=item<=60])
print("%d %.2lf%%"%(alen,100*alen/len(s1)))
alen=len([item for item in s1 if 61<=item])
print("%d %.2lf%%"%(alen,100*alen/len(s1)))