Could someone explain me how this code works line to line? Thanks.

Question

var a=[9,5,2];
for (var i=1;i<3;i++){
a[0]%=a[i];
}
document.write(a[0]);

Answer 1

Just hand trace it.

a[0] %= a[1]
// 9 % 5 is 4
// a[0] now stores 4

a[0] %= a[2]
// 4 % 2 is 0
// a[0] now stores 0

document.write(a[0])
// writes 0

Answer 2

thanks