如何把forEach循环改成for循环感激不尽

Question

如何把下面forEach循环改成for循环：
v.cityData.forEach(function(e){
letname=e.name.substr(0,1);
letlen=e.cities.length;
v.anchorMap[name]=y;
y-=titleHeight+len*itemHeight;
});

Answer 1

for(leti=0;i

Answer 2

for(leti=0,iLen=v.cityData.length;i