let buf = “”;
process.stdin.on(‘readable’, function(){
let c = process.stdin.read();
if (c) buf += c.toString();
})
let reverse = (str)=>{
return str.split(‘’).reverse().join(‘’);
}
process.stdin.on(‘end’, function(){
let lines = buf.split(‘\n’);
for (let i=0;i<lines.length;){
let n = parseInt(lines[i]);
if (n === 0) break;
i;
for(let j=0;j<n;j){
lines[i+j] = reverse(lines[i+j]);
}
let flag = 1, str = ‘’;
for(let k=0;k<lines[i].length;k){
for (let j=1;j<n;j){
if(lines[i][k] !== lines[i+j][k]) flag = 0;
}
if(flag === 0) break;
str += lines[i][k];
}
console.log(reverse(str));
i += n;
}
})