math.ceil 上舍入 Math.floor 下舍入
var x = 99.2000;
var y = 2;
var z= -90.1;
console.log(Math.ceil(x));
console.log(Math.floor(x));
console.log(Math.ceil(z));
console.log(Math.floor(z));
輸出100 99 -90 -91
math.ceil 上舍入 Math.floor 下舍入
var x = 99.2000;
var y = 2;
var z= -90.1;
console.log(Math.ceil(x));
console.log(Math.floor(x));
console.log(Math.ceil(z));
console.log(Math.floor(z));
輸出100 99 -90 -91