let firstList = gets().replace(',', '').split('').map(Number);
let secondList = gets().replace(',', '').split('').map(Number);
let combinedLists = [];
for (let i = 0; i < firstList.length; i++) {
    combinedLists.push(firstList[i], secondList[i]);
}
print(combinedLists.filter(function(element){
    return !Number.isNaN(element);
}).join(','))

// Код 2 започва от тук надолу

let firstList = gets();
let secondList = gets();
let combinedLists = [];
for (let i = 0; i < firstList.length; i++) {
    combinedLists.push(firstList[i], secondList[i]);
}
combinedLists = combinedLists.toString().replace(/,/g, '');
print(combinedLists.toString().split('').join(','));