how to replace some character with certain repeting regex

this is the log

console.log(duckShoot(4, 0.64, '|~~2~~~22~2~~22~2~~~~2~~~|'));

the output must be====>|~~X~~~X2~2~~22~2~~~~2~~~|

here the code i’ve try:

function duckShoot(ammo, aim, ducks) {

    let shot = Math.floor(ammo * aim)

    // console.log(shot);

    return ducks.replace (/2/g, "X")
}

how to make /2/g just replace certain repeating

i wanna make code above same function with this

function duckShoot(ammo, aim, ducks) {

let shot = Math.floor(ammo * aim)

// console.log(shot);

for (let i = 1; i <= shot; i++) {

    ducks = ducks.replace("2", "X");

}

return ducks

}

>Solution :

You can use something like below, where n is the number of occurrences. For n=2, it will replace the first 2 and so on as you call

n = 2;
newTxt = txt.replace(/2/g, s => n && n-- && 'X' || s);

So your function will look like this below

function duckShoot(ammo, aim, ducks) {
  let shot = Math.floor(ammo * aim)
  return ducks.replace(/2/g, s => shot && shot-- && 'X' || s);
}

console.log(duckShoot(4, 0.64, '|~~2~~~22~2~~22~2~~~~2~~~|'))