let array = [,1,,2,,3]; array = array.map((i) => ++i)
let array = [,1,,2,,3];
array = array.map((i) => ++i)
[null,2,null,3,null,4]
[1,2,1,3,1,4]
[NaN,2,NaN,3,NaN,4]
[,2,,3,,4]
