#include<stdio.h>
struct square
{
    int edge;
    int area;
};
int main()
{
    int struct square sq;
    scanf("%d",&sq.edge);
    if(sq.edge<=0)
    {
        printf("Invalid input");
        return 0;
    }
    sq.area=sq.edge*sq.edge;
    printf("%d",sq.area);
}