將數字中的第 k 位關掉
範例
Consider n = 20(00010100), k = 3 The result after turning off the 3rd bit => 00010000 & ^(1<<(3-1)) => 00010000 & ^(1 << 2) => 00010000 => 16s
解決此問題的辦法
步驟 1 − 定義一個方法,其中 n 和 k 為引數,返回型別為 int。
步驟 2 − 對 n & ^(1<<(k-1)) 執行 AND 操作。
步驟 3 − 返回獲得的數字。
範例
package main import ( "fmt" "strconv" ) func TurnOffKthBit(n, k int) int { return n & ^(1 << (k-1)) } func main(){ var n = 20 var k = 3 fmt.Printf("Binary of %d is: %s.\n", n, strconv.FormatInt(int64(n), 2)) newNumber := TurnOffKthBit(n, k) fmt.Printf("After turning off %d rd bit of %d is: %d.\n", k, n, newNumber) fmt.Printf("Binary of %d is: %s.\n", newNumber, strconv.FormatInt(int64(newNumber), 2)) }
輸出
Binary of 20 is: 10100. After turning off 3 rd bit of 20 is 16. Binary of 16 is: 10000.
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