> * ***function caesarCipher(s, k) {

let alpha ="abcdefghijklmnopqrstuvwxyz"
let result=[];
for (let i of s)
{if(i.toUpperCase() == i.toLowerCase()) result.push(i)
for(let j=0; j<alpha.length; j++)
{  
    if(i==alpha[j] ) result.push(alpha[(j+k) % alpha.length])
    else if(i ==alpha[j].toUpperCase() ) result.push(alpha[(j+k) % alpha.length].toUpperCase())

}
}