inp = require('fs').readFileSync('/dev/stdin', 'utf8').trim().split('\n')
N = inp.shift()
l = inp.shift().split(' ')
S = l[0]
T = l[1]
ans = ''
for (i=0;i<S.length;i++) {
    ans += S[i]
    ans += T[i]
}
console.log(ans)