给定大小为N且整数K的数组arr [] ,任务是通过对数组元素执行右移运算,使所有数组元素>K 。
注意:如果不可能使所有数组元素> K ,则打印-1 。
例子:
Input: arr[] = { 21, 22, 23, 19 }, K = 24
Output: { 26, 26, 27, 25 }
Explanation:
arr[0] = 10101. Performing 1 right shift -→ 11010 → 26
arr[1] = 10110. Performing 3 right shift → 11010 → 26
arr[2] = 10111. Performing 1 right shift → 11011 → 27
arr[3] = 10011. Performing 2 right shift → 11001 → 25
Input: arr[] = { 45, 37, 54, 46, 62 }, K = 48
Output: { 54, 50, 54, 53, 62 }
方法:请按照以下步骤解决问题:
- 遍历数组
- 对每个数组元素arr [i]的数字执行右移运算。
- 如果arr [i]> k ,则更新arr [i]并继续。
- 如果任何数组元素arr [i]≤K,则打印-1
- 否则,打印数组arr [] 。
下面是上述方法的实现:
C++
// C++ program to implement
// the above approach
#include
using namespace std;
// Function to find
// MSB of a number
int setBitNumber(int n)
{
// Stores the position of the
// most significant set bit
int k = log2(n);
// Return the position of the
// most significant set bit
return k;
}
// Function to check if all array
// elements are exceeding k or not
bool check(int arr[], int k, int n)
{
// Traverse the array arr
for (int i = 0; i < n; i++) {
// If current element
// does not exceed k
if (arr[i] <= k)
return false;
}
return true;
}
// Function to modify array by
// right shifting digits such that
// all array elements are exceeding k
void modifyArray(int arr[], int k, int n)
{
// Traverse the array
for (int i = 0; i < n; i++) {
// If current element
// exceeds k
if (arr[i] > k)
continue;
else {
// Count bits in the binary
// representation of arr[i]
// MSB of arr[i]
int bits = setBitNumber(arr[i]);
int el = arr[i];
// Perform right shift operations
for (int j = 0; j < bits; j++) {
// If the current element is odd
if (el & 1) {
// Right shift the element
el >>= 1;
// Perform OR with the bitmask
el |= (1 << bits);
}
// If the current element is even
else {
// Right shift the element
el >>= 1;
}
// If current element exceeds k
if (el > k) {
arr[i] = el;
break;
}
}
}
}
// Check if all array elements
// are greater than k or not
if (check(arr, k, n)) {
for (int i = 0; i < n; i++)
cout << arr[i] << " ";
}
else
cout << -1;
}
// Driver Code
int main()
{
int arr[] = { 21, 22, 23, 19 };
// Size of array
int n = sizeof(arr) / sizeof(arr[0]);
int k = 24;
modifyArray(arr, k, n);
return 0;
}
// This code is contributed by subhammahato348.
Java
// Java program to implement
// the above approach
public class GFG
{
// Function to find
// MSB of a number
static int setBitNumber(int n)
{
// Stores the position of the
// most significant set bit
int k = (int)(Math.log(n) / Math.log(2));
// Return the position of the
// most significant set bit
return k;
}
// Function to check if all array
// elements are exceeding k or not
static boolean check(int[] arr, int k, int n)
{
// Traverse the array arr
for (int i = 0; i < n; i++)
{
// If current element
// does not exceed k
if (arr[i] <= k)
return false;
}
return true;
}
// Function to modify array by
// right shifting digits such that
// all array elements are exceeding k
static void modifyArray(int[] arr, int k, int n)
{
// Traverse the array
for (int i = 0; i < n; i++)
{
// If current element
// exceeds k
if (arr[i] > k)
continue;
else
{
// Count bits in the binary
// representation of arr[i]
// MSB of arr[i]
int bits = setBitNumber(arr[i]);
int el = arr[i];
// Perform right shift operations
for (int j = 0; j < bits; j++)
{
// If the current element is odd
if ((el & 1) != 0)
{
// Right shift the element
el >>= 1;
// Perform OR with the bitmask
el |= (1 << bits);
}
// If the current element is even
else
{
// Right shift the element
el >>= 1;
}
// If current element exceeds k
if (el > k)
{
arr[i] = el;
break;
}
}
}
}
// Check if all array elements
// are greater than k or not
if (check(arr, k, n)) {
for (int i = 0; i < n; i++)
System.out.print(arr[i] + " ");
}
else
System.out.print("-1");
}
// Driver code
public static void main(String[] args) {
int[] arr = { 21, 22, 23, 19 };
// Size of array
int n = arr.length;
int k = 24;
modifyArray(arr, k, n);
}
}
// This code is conntrributed by divyesh072019.
Python3
# Python program to implement
# the above approach
import math
# Function to find
# MSB of a number
def setBitNumber(n):
# Stores the position of the
# most significant set bit
k = int(math.log(n, 2))
# Return the position of the
# most significant set bit
return k
# Function to check if all array
# elements are exceeding k or not
def check(arr, k):
# Traverse the array arr
for el in arr:
# If current element
# does not exceed k
if el <= k:
return False
return True
# Function to modify array by
# right shifting digits such that
# all array elements are exceeding k
def modifyArray(arr, k):
# Traverse the array
for i in range(len(arr)):
# If current element
# exceeds k
if arr[i] > k:
continue
else:
# Count bits in the binary
# representation of arr[i]
# MSB of arr[i]
bits = setBitNumber(arr[i])
el = arr[i]
# Perform right shift operations
for j in range(bits):
# If the current element is odd
if el & 1:
# Right shift the element
el >>= 1
# Perform OR with the bitmask
el |= (1 << bits)
# If the current element is even
else:
# Right shift the element
el >>= 1
# If current element exceeds k
if el > k:
arr[i] = el
break
# Check if all array elements
# are greater than k or not
if check(arr, k):
return arr
else:
return -1
# Driver Code
arr = [21, 22, 23, 19]
k = 24
print(modifyArray(arr, k))
C#
// C# program to implement
// the above approach
using System;
class GFG
{
// Function to find
// MSB of a number
static int setBitNumber(int n)
{
// Stores the position of the
// most significant set bit
int k = (int)(Math.Log(n, 2));
// Return the position of the
// most significant set bit
return k;
}
// Function to check if all array
// elements are exceeding k or not
static bool check(int[] arr, int k, int n)
{
// Traverse the array arr
for (int i = 0; i < n; i++)
{
// If current element
// does not exceed k
if (arr[i] <= k)
return false;
}
return true;
}
// Function to modify array by
// right shifting digits such that
// all array elements are exceeding k
static void modifyArray(int[] arr, int k, int n)
{
// Traverse the array
for (int i = 0; i < n; i++)
{
// If current element
// exceeds k
if (arr[i] > k)
continue;
else
{
// Count bits in the binary
// representation of arr[i]
// MSB of arr[i]
int bits = setBitNumber(arr[i]);
int el = arr[i];
// Perform right shift operations
for (int j = 0; j < bits; j++)
{
// If the current element is odd
if ((el & 1) != 0)
{
// Right shift the element
el >>= 1;
// Perform OR with the bitmask
el |= (1 << bits);
}
// If the current element is even
else
{
// Right shift the element
el >>= 1;
}
// If current element exceeds k
if (el > k)
{
arr[i] = el;
break;
}
}
}
}
// Check if all array elements
// are greater than k or not
if (check(arr, k, n)) {
for (int i = 0; i < n; i++)
Console.Write(arr[i] + " ");
}
else
Console.Write("-1");
}
// Driver Code
public static void Main()
{
int[] arr = { 21, 22, 23, 19 };
// Size of array
int n = arr.Length;
int k = 24;
modifyArray(arr, k, n);
}
}
// This code is contributed by chitranayal.
Javascript
输出:
[26, 26, 27, 25]
时间复杂度: O(N)
辅助空间: O(1)