Envío 4262

Código

var readline = require('readline');
var rl = readline.createInterface({
  input: process.stdin,
  output: process.stdout,
});
var res = "";
var bn;
var carry = 0;
rl.on("line", function(line) {

if(bn === undefined){bn = line; return;}

for(var i = Math.max(bn.length-1,line.length-1); i >= 0 ; i--){
var current = carry
if(bn.length > i){current += parseInt(bn[i])}
if(line.length > i){current += parseInt(line[i])}
res = (current%10) + res
carry = parseInt(res/10)

}
console.log((carry > 0? carry :"")+res)
});