programming-examples/c++/Combinational_Problems/C++ Program to Find the peak element of an array using Binary Search approach.cpp
2019-11-15 12:59:38 +01:00

72 lines
1.2 KiB
C++

/*
* C++ Program to Find the peak element of an array using Binary Search approach
*/
#include<iostream>
#include<conio.h>
using namespace std;
void max_heapify(int *a, int i, int n)
{
int j, temp;
temp = a[i];
j = 2 * i;
while (j <= n)
{
if (j < n && a[j + 1] > a[j])
j = j + 1;
if (temp > a[j])
break;
else if (temp <= a[j])
{
a[j / 2] = a[j];
j = 2 * j;
}
}
a[j / 2] = temp;
return;
}
void build_maxheap(int *a, int n)
{
int i;
for(i = n / 2; i >= 1; i--)
{
max_heapify(a, i, n);
}
}
int main()
{
int n, i, x;
cout<<"enter no of elements of array\n";
cin>>n;
int a[20];
for (i = 1; i <= n; i++)
{
cout<<"enter element"<<(i)<<endl;
cin>>a[i];
}
build_maxheap(a, n);
cout<<"Maximum element is "<<a[1]<<endl;
getch();
}
/*
enter no of elements of array
8
enter element1
1
enter element2
7
enter element3
3
enter element4
6
enter element5
2
enter element6
6
enter element7
4
enter element8
9
Maximum element is 9