#include <iostream.h>#include <stdio.h>int a[]={2,1,2,3,4,5,6,7,8,9};float f(int n){ if(1==n) return (float)a[0]; else return((float)((n-1)*f(n-1)+a[n-1])/n);}main(){ int n=5; printf("f(%d)=%f\n",n,f(n));}