Data Structure
Networking
RDBMS
Operating System
Java
MS Excel
iOS
HTML
CSS
Android
Python
C Programming
C++
C#
MongoDB
MySQL
Javascript
PHP
Physics
Chemistry
Biology
Mathematics
English
Economics
Psychology
Social Studies
Fashion Studies
Legal Studies
- Selected Reading
- UPSC IAS Exams Notes
- Developer's Best Practices
- Questions and Answers
- Effective Resume Writing
- HR Interview Questions
- Computer Glossary
- Who is Who
Program to find the maximum number in rotated list in C++
Suppose there is an array, and that is sorted, consider that array is rotated at some pivot, that is unknown to us. So we have to find the maximum from that rotated array. So if the array is like[3,4,5,1,2], then the output will be 5.
To solve this, we will follow these steps −
low := 0 and high := last index of array, n := size of array, ans := 0
while low <= high
mid := low + (high - low)/2
if arr[low] < arr[mid], then ans := maximum of ans and arr[low], low := mid + 1
else if arr[high] > arr[mid], then ans := maximum of ans and arr[mid], high := mid – 1
else if low = mid, then ans := maximum of ans and arr[low], low := mid + 1
else if high = mid, then ans := maximum of ans and arr[high], high := mid - 1
return ans
Let us see the following implementation to get better understanding −
Example
#include <bits/stdc++.h>
using namespace std;
class Solution {
public:
int search(vector <int>& arr, int low, int high){
if(low == high){
return arr[low];
}
int mid = low + (high - low) / 2;
int ans = 0;
if(arr[low] < arr[mid]){
ans = max(arr[low], search(arr, mid, high));
}
else if (arr[high] > arr[mid]){
ans = max(arr[mid], search(arr, low, mid));
}
else if(arr[low] == arr[mid]){
ans = max(arr[low], search(arr, low + 1, high));
}
else if(arr[high] == arr[mid]){
ans = max(arr[high], search(arr, low, high - 1));
}
return ans;
}
int findMax(vector<int>& nums) {
return search(nums, 0, nums.size() - 1);
}
};
main(){
Solution ob;
vector<int> v = {4,5,5,5,6,8,2,3,4};
cout <<(ob.findMax(v));
}Input
[4,5,5,5,6,8,2,3,4]
Output
8
60 Views
