var readlineSync = require('readline-sync');

// Wait for user's response.
var i = parseInt(readlineSync.question('input i:\n'));
var j = parseInt(readlineSync.question('input j:\n'));

if (isNaN(i) || isNaN(j))
{
    console.error("invalid input");
    return;
}
console.log('i + j = ' + (i+j));