function Main(input) {
  var nums = input.split('\n');
  var strings = nums[1].split(' ');
  
  let ans = [];
  
  for (let i = 0; i < nums[0]; i++) {
    ans.push(strings[0][i]);
    ans.push(strings[1][i]);
  }
  
  console.log(ans.join(''));
}
Main(require('fs').readFileSync('/dev/stdin', 'utf8'));