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<title>Document</title>
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// 1. 交换两个变量
let n1 = 5;
let n2 = 6;
let tmp;
tmp = n1;
n1 = n2;
n2 = tmp;
console.log(n1 ,n2);
// 2. 交换两个变量值，不使用第三个变量
let m1 = 5;
let m2 = 6;
m1 = m1 + m2; // 5 + 6 = 11
m2 = m1 - m2; // 11 - 6 = 5
m1 = m1 - m2; // 11 - 5 = 6
console.log(m1, m2)
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