写一个 mySetInterVal(fn, a, b),每次间隔 a,a+b,a+2b,...,a+nb 的时间，然后写一个 myClear，停止上面的 mySetInterVal

function mySetInterVal(fn, a, b) {
    let time = 0;
    let timer = {
        id: -1
    };

    const start = (timeout) => {
        timer.id = setTimeout(() => {
            fn();
            time++;
            start(timeout + time * b);
        }, timeout)
    }

    start(a);

    return timer;
}

function myClear(timer){
    clearTimeout(timer.id)
}

var a = new mySetInterVal(() => {
    console.log(`time: ${new Date().getSeconds()}`)
}, 100, 150);

myClear(a)