不使用条件/按位/三元运算符的数组中最大的
定义一个函数int max(int a[], int n) 从包含 n 个元素的整数数组中返回最大整数(不使用条件/按位/三元运算符/库函数来查找最大
例子:
Input : arr[] = {16, 14, 15, 17, 9}
Output : 17
Input : arr[] = {10, 13, 11, 13}
Output : 13
这个想法类似于最多四个数字。
我们使用“(x – y + abs(x – y))”的值将是 0 的事实,即 x 小于或等于 y。我们将此值用作大小为 2 的数组中的索引来选择最大值。一旦我们找到了两个元素的最大值,我们就可以使用相同的技术来找到所有元素的最大值。
C++
// CPP program to find largest in an array
// without conditional/bitwise/ternary/ operators
// and without library functions.
#include
using namespace std;
int maxArray(int a[], int n)
{
int tmp[2];
tmp[0] = a[0];
for (int i = 1; i < n; i++) {
tmp[1] = a[i];
swap(tmp[0], tmp[bool(abs(tmp[1] - tmp[0]) +
tmp[1] - tmp[0])]);
}
return tmp[0];
}
// Driver code
int main()
{
int a[] = { 15, 11, 17, 16, 10 };
int n = sizeof(a) / sizeof(a[0]);
cout << maxArray(a, n);
return 0;
}
Java
// JAVA program to find largest in an array
// without conditional/bitwise/ternary/ operators
// and without library functions.
import java.util.*;
class GFG
{
static int maxArray(int a[], int n)
{
int []tmp = new int[2];
tmp[0] = a[0];
for (int i = 1; i < n-1; i++) {
tmp[1] = a[i];
int temp = tmp[0];
tmp[0] = tmp[(Math.abs(tmp[1] - tmp[0]) +
tmp[1] - tmp[0])%2+1];
tmp[(Math.abs(tmp[1] - tmp[0]) +
tmp[1] - tmp[0])%2+1] = temp;
}
return tmp[1];
}
// Driver code
public static void main(String[] args)
{
int a[] = { 15, 11, 17, 16, 10 };
int n =a.length;
System.out.print(maxArray(a, n));
}
}
// This code is contributed by umadevi9616
Python3
# Python 3 program to find largest in an array
# without conditional/bitwise/ternary/ operators
# and without library functions.
def maxArray(a, n):
tmp = [a[i] for i in range(len(a))]
tmp[0] = a[0]
for i in range(1,n,1):
tmp[1] = a[i]
temp = tmp[int(bool(abs(tmp[1] - tmp[0]) +
tmp[1] - tmp[0]))]
tmp[int(bool(abs(tmp[1] - tmp[0]) +
tmp[1] - tmp[0]))] = tmp[0]
tmp[0] = temp
return tmp[0]
# Driver code
if __name__ == '__main__':
a = [15, 11, 17, 16, 10]
n = len(a)
print(maxArray(a, n))
# This code is contributed by
# Surendra_Gangwar
C#
// C# program to find largest in an array
// without conditional/bitwise/ternary/ operators
// and without library functions.
using System;
public class GFG {
static int maxArray(int[] a, int n)
{
int[] tmp = new int[2];
tmp[0] = a[0];
for (int i = 1; i < n - 1; i++) {
tmp[1] = a[i];
int temp = tmp[0];
tmp[0] = tmp[(Math.Abs(tmp[1] - tmp[0]) + tmp[1]
- tmp[0]) % 2 + 1];
tmp[(Math.Abs(tmp[1] - tmp[0]) + tmp[1]
- tmp[0]) % 2 + 1] = temp;
}
return tmp[1];
}
// Driver code
public static void Main(String[] args)
{
int[] a = { 15, 11, 17, 16, 10 };
int n = a.Length;
Console.Write(maxArray(a, n));
}
}
// This code is contributed by umadevi9616
Javascript
输出:
17