题解

#include<iostream>
#include<string>
using namespace std;
int main(){
    int n;
    cin>>n;
    string s1,s2;
    cin>>s1>>s2;
    for(int i=0;i<n;i+=2){
        s1[i]=s2[i];
    }
    for(int i=0;i<n;i++){
        cout<<s1[i];
    }
    return 0;
}