可能重複:
What is the difference between Linear search and Binary search?爪哇 - 比較線性搜索和二分搜索的性能
收件從0到100生成的範圍 內20個隨機整數的程序。按降序排列數組。然後,接受來自用戶的整數輸入 。然後,使用此 數字搜索陣列。比較線性搜索和二進制搜索的性能。
這裏是我的代碼
import java.util.Arrays;
import java.util.Scanner;
public class search {
public static void main(String args[]) {
int[] num = new int[20];
for (int i = 0; i < num.length; i++) {
num[i] = (int) (Math.random() * 101);
}
System.out.println("A list of 20 random intergers with 0 - 100");
System.out.println(Arrays.toString(num));
for (int j = 1; j < num.length; j++) {
for (int k = 0; k < num.length - 1; k++) {
if (num[k] < num[k + 1]) {
int hold = num[k + 1];
num[k + 1] = num[k];
num[k] = hold;
}
}
}
System.out.println("Array in descending order");
System.out.println(Arrays.toString(num));
Scanner input = new Scanner(System.in);
System.out.print("Enter a number to search: ");
int num2 = input.nextInt();
int loop = 0;
for (int cnt = 0; cnt < num.length; cnt++)
{
if (num[cnt] == num2)
{
loop = cnt;
System.out.println(num2+ " found");
}
}
System.out.println("Linear search - "+loop+ " loop(s)");
int loop2 = 0;
int low = 0; // low element subscript
int high = num.length - 1; // high element subscript
int middle; // middle element subscript
while (low <= high) {
middle = (low + high)/2;
if (num2 == num[ middle ]) {
}
else if (num2 > num[ middle ])
{
low = middle +1;
loop2++;
}
else{
high = middle - 1;
loop2++;
}
}
System.out.println("Binary search - "+loop2+ " loop(s)");
}
}
我可以得到線性搜索的環數。但是,我無法獲得二進制搜索循環數。
你是什麼意思,你「無法得到它」?你有什麼錯誤嗎? – alestanis
「比較線性搜索和二進制搜索的性能」可能也意味着執行比較的次數,而不是計算循環次數。 – Sujay
System.out.println(「Binary search - 」+ loop2 +「loop(s)」)的輸出是什麼;'? – mcalex