给定一个数组,编写一个程序,将最小数量(应大于0 )添加到数组中,以使数组的总和变为偶数。
例子:
Input : 1 2 3 4 5 6 7 8
Output : 2
Explanation : Sum of array is 36, so we
add minimum number 2 to make the sum even.
Input : 1 2 3 4 5 6 7 8 9
Output : 1
方法1(计算总和)。我们计算数组中所有元素的总和,然后可以检查总和是否等于最小数为2,否则最小数为1。如果总和超过允许的限制,则此方法可能导致溢出。
方法2。我们不计算数量之和,而是保留数组中元素的奇数个数。如果存在的奇数计数为偶数,则返回2,否则返回1。
例如–数组包含:1 2 3 4 5 6 7
奇数计数为4。我们知道奇数的偶数之和为偶数。而且偶数之和始终是偶数(这就是为什么我们不保留偶数的计数)。
C++
// CPP program to add minimum number
// so that the sum of array becomes even
#include
using namespace std;
// Function to find out minimum number
int minNum(int arr[], int n)
{
// Count odd number of terms in array
int odd = 0;
for (int i = 0; i < n; i++)
if (arr[i] % 2)
odd += 1;
return (odd % 2)? 1 : 2;
}
// Driver code
int main()
{
int arr[] = { 1, 2, 3, 4, 5, 6, 7, 8, 9 };
int n = sizeof(arr) / sizeof(arr[0]);
cout << minNum(arr, n) << "n";
return 0;
}
Java
// Java program to add minimum number
// so that the sum of array becomes even
class GFG
{
// Function to find out minimum number
static int minNum(int arr[], int n)
{
// Count odd number of terms in array
int odd = 0;
for (int i = 0; i < n; i++)
if (arr[i] % 2 != 0)
odd += 1;
return ((odd % 2) != 0)? 1 : 2;
}
// Driver method to test above function
public static void main(String args[])
{
int arr[] = { 1, 2, 3, 4, 5, 6, 7, 8, 9 };
int n = arr.length;
System.out.println(minNum(arr, n));
}
}
Python
# Python program to add minimum number
# so that the sum of array becomes even
# Function to find out minimum number
def minNum(arr, n):
# Count odd number of terms in array
odd = 0
for i in range(n):
if (arr[i] % 2):
odd += 1
if (odd % 2):
return 1
return 2
# Driver code
arr = [1, 2, 3, 4, 5, 6, 7, 8, 9]
n = len(arr)
print minNum(arr, n)
C#
// C# program to add minimum number
// so that the sum of array becomes even
using System;
class GFG
{
// Function to find out minimum number
static int minNum(int []arr, int n)
{
// Count odd number of terms in array
int odd = 0;
for (int i = 0; i < n; i++)
if (arr[i] % 2 != 0)
odd += 1;
return ((odd % 2) != 0)? 1 : 2;
}
// Driver Code
public static void Main()
{
int []arr = {1, 2, 3, 4, 5, 6, 7, 8, 9};
int n = arr.Length;
Console.Write(minNum(arr, n));
}
}
// This code is contributed by Nitin Mittal.
PHP
Javascript
C++
// CPP program to add minimum number
// so that the sum of array becomes even
#include
using namespace std;
// Function to find out minimum number
int minNum(int arr[], int n)
{
// Count odd number of terms in array
bool odd = 0;
for (int i = 0; i < n; i++)
if (arr[i] % 2)
odd = !odd;
if (odd)
return 1;
return 2;
}
// Driver code
int main()
{
int arr[] = { 1, 2, 3, 4, 5, 6, 7, 8, 9 };
int n = sizeof(arr) / sizeof(arr[0]);
cout << minNum(arr, n) << "n";
return 0;
}
Java
// Java program to add minimum number
// so that the sum of array becomes even
class GFG
{
// Function to find out minimum number
static int minNum(int arr[], int n)
{
// Count odd number of terms in array
Boolean odd = false;
for (int i = 0; i < n; i++)
if (arr[i] % 2 != 0)
odd = !odd;
if (odd)
return 1;
return 2;
}
//Driver method to test above function
public static void main(String args[])
{
int arr[] = { 1, 2, 3, 4, 5, 6, 7, 8, 9 };
int n = arr.length;
System.out.println(minNum(arr, n));
}
}
Python
# Python program to add minimum number
# so that the sum of array becomes even
# Function to find out minimum number
def minNum(arr, n):
# Count odd number of terms in array
odd = False
for i in range(n):
if (arr[i] % 2):
odd = not odd
if (odd):
return 1
return 2
# Driver code
arr = [1, 2, 3, 4, 5, 6, 7, 8, 9]
n = len(arr)
print minNum(arr, n)
C#
// C# program to add minimum number
// so that the sum of array becomes even
using System;
class GFG
{
// Function to find out minimum number
static int minNum(int []arr, int n)
{
// Count odd number of terms in array
bool odd = false;
for (int i = 0; i < n; i++)
if (arr[i] % 2 != 0)
odd = !odd;
if (odd)
return 1;
return 2;
}
//Driver Code
public static void Main()
{
int []arr = {1, 2, 3, 4, 5, 6, 7, 8, 9};
int n = arr.Length;
Console.Write(minNum(arr, n));
}
}
// This code is contributed by Nitin Mittal.
PHP
输出:
1
方法3。我们还可以改进2方法,我们不需要保留存在的奇数个元素的数量。我们可以使用一个布尔变量(初始化为0)。每当我们在数组中找到奇数元素时,我们都会对布尔变量执行NOT(!)操作。此逻辑运算符将布尔变量的值取反(意味着如果它为0,则将变量转换为1,反之亦然)。
例如–数组包含:1 2 3 4 5
说明:变量初始化为0。
遍历数组
1是奇数,对变量应用NOT运算,现在变量变为1。
2是偶数,无操作。
3是奇数,在变量中应用NOT运算,现在变量变为0。
4是偶数,无操作。
5是奇数,对变量应用NOT运算,现在变量变为1。
如果变量值为1,则表示存在奇数个奇数元素,使元素之和等于的最小数加1。
其他最小数字为2。
C++
// CPP program to add minimum number
// so that the sum of array becomes even
#include
using namespace std;
// Function to find out minimum number
int minNum(int arr[], int n)
{
// Count odd number of terms in array
bool odd = 0;
for (int i = 0; i < n; i++)
if (arr[i] % 2)
odd = !odd;
if (odd)
return 1;
return 2;
}
// Driver code
int main()
{
int arr[] = { 1, 2, 3, 4, 5, 6, 7, 8, 9 };
int n = sizeof(arr) / sizeof(arr[0]);
cout << minNum(arr, n) << "n";
return 0;
}
Java
// Java program to add minimum number
// so that the sum of array becomes even
class GFG
{
// Function to find out minimum number
static int minNum(int arr[], int n)
{
// Count odd number of terms in array
Boolean odd = false;
for (int i = 0; i < n; i++)
if (arr[i] % 2 != 0)
odd = !odd;
if (odd)
return 1;
return 2;
}
//Driver method to test above function
public static void main(String args[])
{
int arr[] = { 1, 2, 3, 4, 5, 6, 7, 8, 9 };
int n = arr.length;
System.out.println(minNum(arr, n));
}
}
Python
# Python program to add minimum number
# so that the sum of array becomes even
# Function to find out minimum number
def minNum(arr, n):
# Count odd number of terms in array
odd = False
for i in range(n):
if (arr[i] % 2):
odd = not odd
if (odd):
return 1
return 2
# Driver code
arr = [1, 2, 3, 4, 5, 6, 7, 8, 9]
n = len(arr)
print minNum(arr, n)
C#
// C# program to add minimum number
// so that the sum of array becomes even
using System;
class GFG
{
// Function to find out minimum number
static int minNum(int []arr, int n)
{
// Count odd number of terms in array
bool odd = false;
for (int i = 0; i < n; i++)
if (arr[i] % 2 != 0)
odd = !odd;
if (odd)
return 1;
return 2;
}
//Driver Code
public static void Main()
{
int []arr = {1, 2, 3, 4, 5, 6, 7, 8, 9};
int n = arr.Length;
Console.Write(minNum(arr, n));
}
}
// This code is contributed by Nitin Mittal.
的PHP
输出 :
1