#include<iostream>
#include<conio.h>
using namespace std;
void main()
{
	int suma, n, numimpar;
	do
	{
	    cout << "Ingrese el valoir de n";cin >> n;
	} while (n<1);
	suma = 0;
	numimpar = 1;
	while (numimpar <= n)
	{
		suma = suma + numimpar;
		numimpar = numimpar + 2;
	}
	cout << "Suma=" << suma;
	_getch();
}