1到n位数字,二进制表示中没有连续的1?
在此问题中,我们必须找到一些没有连续1的二进制数。在一个3位二进制字符串中,存在三个具有连续1的二进制数字011、110、111,并且有五个没有连续1的数字。因此,对3位数字应用此算法后,答案将为5。
如果a[i]是二进制数的集合,其位数为i,并且不包含任何连续的1,b[i]是二进制数的集合,其中位数为i,并且包含连续的1,然后有类似的递归关系-
a[i] := a[i - 1] + b[i - 1]
b[i] := a[i - 1]
输入值
该算法为二进制数获取位数。让输入为4。
输出结果
它返回不具有连续1的二进制字符串的数量。
此处的结果是−8。(有8个二进制字符串,没有连续的1)
算法
countBinNums(n)
Input: n is the number of bits. Output: Count how many numbers are present which have no consecutive 1. Begin define lists with strings ending with 0 and ending with 1 endWithZero[0] := 1 endWithOne[0] := 1 for i := 1 to n-1, do endWithZero[i] := endWithZero[i-1] + endWithOne[i-1] endWithOne[i] := endWithZero[i-1] done return endWithZero[n-1] + endWithOne[n-1] End
示例
#include <iostream> using namespace std; int countBinNums(int n) { int endWithZero[n], endWithOne[n]; endWithZero[0] = endWithOne[0] = 1; for (int i = 1; i < n; i++) { endWithZero[i] = endWithZero[i-1] + endWithOne[i-1]; endWithOne[i] = endWithZero[i-1]; } return endWithZero[n-1] + endWithOne[n-1]; } int main(){ int n; cout << "Enter number of bits: "; cin >> n; cout << "Number of binary numbers without consecutive 1's: "<<countBinNums(n) << endl; return 0; }
输出结果
Enter number of bits: 4 Number of binary numbers without consecutive 1's: 8