C++ Programming Code Examples
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Find Second Smallest of n Elements with Given Complexity Constraint
/* Find Second Smallest of n Elements with Given Complexity Constraint
- Traverse the data array linearly and find the second smallest element.
- The time complexity of the algorithm is O(n).
- Linearly traverse the data array.
- Keep track of the smallest number.
- Simultaneously keep updating the second smallest number also.
- Exit. */
#include<iostream>
using namespace std;
// A function to calculate second.
int SecondSmallest(int *a, int n)
{
int s, ss, i;
// A variable 's' keeping track of smallest number.
s = a[0];
// A variable 'ss' keeping track of second smallest number.
ss = a[0];
// Traverse the data array.
for(i = 1; i < n; i++)
{
// If array element is lesser than current 's' value then update.
if(s > a[i])
{
ss = s;
s = a[i];
}
// Otherwise the number can be second smallest number so check for the condition and update 'ss'.
else if(ss > a[i])
{
ss = a[i];
}
}
// Return second smallest number.
return ss;
}
int main()
{
int n, i;
cout<<"Enter the number of element in dataset: ";
cin>>n;
int a[n];
// Take input.
for(i = 0; i < n; i++)
{
cout<<"Enter "<<i+1<<"th element: ";
cin>>a[i];
}
// Print the result.
cout<<"\n\nThe second Smallest number of the given data array is: "<<SecondSmallest(a, n);
return 0;
}
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