"use strict";
const Main = (input) =>{
   let xs = input.trim().split('\n');
   let xs1 = xs[1].trim().split(' ');
   let N = xs[0];
   let S = xs1[0].trim().split('');
   let T = xs1[1].trim().split('');
   let ans = [];
   for(let i=0; i<N; i++){
      ans.push(S[i]+T[i]);
   }
   let ans1 = '';
   for(let i=0; i<N; i++){
      ans1+=ans[i];
   }
   console.log(ans1);
   
}
Main(require('fs').readFileSync('/dev/stdin','utf8'));