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<title>Document</title>
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<!-- 算数运算符
+ - * / %-->
</body>
<script>
console.log(2 + 3);//5
console.log("2" + 3);//23
console.log(2 + true);//3
console.log("2" + true);//2true
console.log(2 + null); //2
console.log(2 + undefined);//NaN(Not a Number) 非数字
console.log("2" + undefined);//2undefined
// 1.当加号两侧同时为数字，加法运算
// 2.当加号任何一侧有字符串，字符串拼接
var a = 10, b = "hello";
console.log(a + b);//10hello
// 1.当加号两侧同时为数字，加法运算
// 2.当加号任何一侧有字符串，字符串拼接
// +
console.log(2 + 4);//6
console.log(2 + 4 + "=");//6=
console.log(2 + 4 + "=" + 3 + 3);//6=33
console.log(2 + 4 + "=" + (3 + 3));//6=6
// -
console.log(2 - 1);//1
console.log(2 - 3);//-1
console.log(2 - false);//2
console.log(23 - "3");//20
console.log("23" - "3");//20
console.log(2 - null);//2
console.log(2 - undefined);//NaN
console.log(2 - "abc");//NaNr
//*
console.log(2 * 1);//2
console.log(2 * 3);//3
console.log(2 * false);//0
console.log(23 * "3");//69
console.log("23" * "3");//69
console.log(2 * null);//0
console.log(2 * undefined);//NaN
console.log(2 * "abc");//NaN
//a+=1;
//a++; //a+=1 a = a + 1
// ++a;
// console.1og(a);
var a = 10;
console.log(a);//10
console.log(a++);//10
console.log(a);//11
var b = 10;
console.log(b);//10
console.log(++b);//11
console.log(b);//11
// 取余
// console.log(10 % 2);//0
console.log(10 % 3);//1
// 1.当加号两侧同时为数字，加法运算
// 2.当加号任何一侧有字符串，字符串拼接
// 一元运算符:一个运算符，一个运算子 a++ ++a
// 二元运算符:一个运算符，二个运算子 a+b a +=10
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