Array problem : find missing value between 1 to 100.

January 29, 2020   C++ Programming , Interview Questions

This is the most asked question in coding interviews. The interviewer will ask you to provide a solution to a problem in which you have an array ranged between 1 to 100 and you have to find a missing element in the given array.

The solution to this problem is very simple ..

you have to follow these two steps to get a solution to a given problem.

1.) find some elements between 1 to 100.

use formula : n*(n+1)/2;  where n=100;

2.) find some of original array.

use : sum=sum+a[i] ;

program for given problem using c++ :

#include<iostream>
#include<array>
using namespace std;
int findMissingElement(array<int,10>a1 ,int n){
 int ActualSum=0;
 int ExpectedSum=n*(n-1)/2;
 for(int i=0;i<n;i++){
  ActualSum=ActualSum+a1.at(i);
 }
 return(ExpectedSum-ActualSum);
}
int main(){
 array<int,10> ar={1,2,3,4,5,7,8,9};
 int fx=findMissingElement(ar,10);
 cout<<fx;
 return 0;

}