// 苹果7的分辨率为1080x1920像素
var resolution = "1080x1920";
var pixels = resolution.split("x").map(function(value) {
return parseInt(value);
}).join("x");
var pixelCount = pixels.split("").reduce(function(total, value) {
return total * parseInt(value);
}, 1);
document.write(pixelCount);