js 浮点数运算的误差

//浮点数运算 会有问题(精度差)
let num = 0.1+0.2          //0.30000000000000004

console.log(0.07*100)     //7.000000000000001

console.log(num == 0.3)   //不相等 false  浮点数的运算会有问题 尽量避免浮点数运算
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