C++ Exercises: Find the first repeating element in an array of integers
C++ Array: Exercise-24 with Solution
Write a C++ program to find the first repeating element in an array of integers.
Pictorial Presentation:
Sample Solution:
C++ Code :
#include<iostream>
using namespace std;
int first_repeating_element(int array1[], int s1)
{
int min_val = -1;
set<int> result;
for (int i = s1 - 1; i >= 0; i--)
{
if (result.find(array1[i]) != result.end())
min_val = i;
else
result.insert(array1[i]);
}
if (min_val != -1)
return array1[min_val];
else
return 0;
}
int main()
{
int array1[] = {3, 1, 5, 1, 5, 7, 9, 7, 9};
int fre;
int s1 = sizeof(array1) / sizeof(array1[0]);
cout << "Original array: ";
for (int i=0; i < s1; i++)
cout << array1[i] <<" ";
fre = first_repeating_element(array1, s1);
cout <<"\nFirst repeating element: " << fre;
return 0;
}
Sample Output:
Original array: 3 1 5 1 5 7 9 7 9 First repeating element: 1
Flowchart:
C++ Code Editor:
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