
面试李组长为您分享以下优质知识
二进制与五进制的转换及运算规则如下:
一、二进制转十进制
二进制数通过位权展开法转换为十进制,公式为:
$$
a_n times 2^n + a_{n-1} times 2^{n-1} + cdots + a_1 times 2^1 + a_0 times 2^0
$$
例如:二进制 `1011010.011` 转换为十进制:
$$
1 times 2^6 + 0 times 2^5 + 1 times 2^4 + 1 times 2^3 + 0 times 2^2 + 1 times 2^1 + 0 times 2^0 + 0 times 2^{-1} + 1 times 2^{-2} + 1 times 2^{-3} = 86.375
$$
二、十进制转二进制
除以2取余,倒序排列。例如:5 → 2余1 → 1余0 → 101。
乘以2取整,顺序排列。例如:0.31 → 0.62取整0 → 0.25取整0 → 0.125取整1 → 0.0625取整0 → 0.03125取整0 → 0.015625取整0 → 0.0078125取整0 → 0.00390625取整0 → 0.001953125取整0 → 0.0009765625取整0 → 0.00048828125取整0 → 0.000244140625取整0 → 0.0001220703125取整0 → 0.00006103515625取整0 → 0.000030517578125取整0 → 0.0000152587890625取整0 → 0.00000762939453125取整0 → 0.000003814697265625取整0 → 0.0000019073486328125取整0 → 0.00000095367431640625取整0 → 0.000000476837158203125取整0 → 0.0000002384185791015625取整0 → 0.00000011920928955078125取整0 → 0.000000059604644775390625取整0 → 0.0000000298023223876953125取整0 → 0.000000014901161193847656取整0 → 0.000000007450580596923828取整0 → 0.000000003725290298461914取整0 → 0.000000001862645149230957取整0 → 0.0000000009313225746154785取整0 → 0.00000000046566128730773925取整0 → 0.00000000023283064365386962