数据结构
网络
RDBMS
操作系统
Java
MS Excel
iOS
HTML
CSS
Android
Python
C 编程
C++
C#
MongoDB
MySQL
Javascript
PHP
物理
化学
生物
数学
英语
经济
心理学
社会研究
时尚研究
法律研究C++ 程序示例——执行统一二分搜索
在统一二分搜索中，我们使用查找表实现了二分搜索。它改进了二分搜索，因为查找表比移位和加法更快。此方法的时间复杂度是 O(log(n))。
算法
Begin Assign the data to the array in a sorted manner. Calculate the maximum length of lookup array and declare a new array ‘del’. Assign the values to the lookup array as n/2, n/4 and so on till ‘0’, where n is the length of the data array. Call UniBinarySearch() function. Assign mid to the value at ‘0’ index of ‘dl’ array and compare key to the value at mid index. If key is equal then return the index value to the main. If index value in ‘dal’ is zero then the element is not there, return - 1 to main. If it is lesser, subtract next value stored in ‘dal’ array and shift the pointer to next value in ‘dal’ array. If it is greater, add next value stored in ‘dal’ array and shift the pointer to next value in ‘dal’ array. print the index value returned by the function and ask for user’s choice to search more. End
示例代码
#include<iostream>
using namespace std;
void lookUpArray(int *a, int N) {
int power = 1, i = 0;
do {
int half = power;
power *= 2;
a[i] = (N+half)/power;
i++;
} while (a[i-1] != 0);
}
int UniBinarySearch(int *a, int *dal, int key) {
int i = d[0]-1, d = 0;
flag:
if (key == a[i])
return i;
else if (dal[d] == 0)
return -1;
else {
if (key < a[i]) {
i -= dal[++d];
goto flag;
}
else {
i += dal[++d];
goto flag;
}
}
}
int main(void) {
int i, n = 10, d = 0, pow = 1, index;
char ch;
int a[10] = {2,6,7, 10, 12, 14, 12, 16,20, 26};
while(pow <= n) {
pow *=2;
d++;
}
int del[d];
lookUpArray(d, n);
up:
cout<<"\nEnter the Element to be searched: ";
cin>>n;
index = UniBinarySearch(a, del, n);
if (index == -1)
cout<<"\nItem not found";
else
cout<<"\nItem "<<n<<" found at "<<index+1<<" position";
cout<<"\n\n\tDo you want to search more...enter choice(y/n)?";
cin>>ch;
if(ch == 'y' || ch == 'Y')
goto up;
return 0;
}输出
Enter the Element to be searched: 7 Item 7 found at 3 position Do you want to search more...enter choice(y/n)?y Enter the Element to be searched: 21 Item not found Do you want to search more...enter choice(y/n)?
更新于： 2019 年 7 月 30 日
281 次浏览
广告