//n阶勒让德多项式
#include<stdio.h>
int main()
{
float prond(float x,int n);
float x;
int n;
scanf("x=%f,n=%d",&x,&n);
printf("The result is :\n");
printf("%.2f ",prond(x,n));
return 0;
}
float prond(float x,int n)
{
float c;
if(n>1)
c=((2*n-1)*x-prond(x,n-1)-(n-1)*prond(x,n-2))/n;
else if(n==1)
c=x;
else
c=1;
return c;
}