function shiftEachLetterNPlacesUp(str: string, N: number) {
str = str.toLowerCase();
let result: string = '';
let charcode: number = 0;
let size: number = str.length;
for (let i: number = 0; i < size; i++) {
charcode = (str[i].charCodeAt(0)) + N;
result += String.fromCharCode(charcode);
}
return result;
}
console.log(shiftEachLetterNPlacesUp('afkq', 3));
/*
run:
"dint"
*/