// standard deviation
#include <iostream> 
#include <cstdlib>
#include <cmath>
using namespace std;
int main(int argc, char *argv[])
{ int i, N=5, x, sumA, flag=0;
  double m,s,sumA2;
  int A[N]; // pinakas me 100 stoixeia
  for (i=0; i<N; i++) {
       cout<<"DOSE TIMH GIA A["<<i<<"]: ";
       cin>>A[i]; }
  cout<<"DOSE TIMH GIA x: ";
  cin>>x;     
   // anazhthsh thesewn tou x              
   for (i=0; i<N; i++)
     if (x==A[i]) {
     cout<<"To "<<x<<" einai sthn thesh "<<i+1<<endl;
     flag=1;
     } 
   if (flag==0) cout<<"To "<<x<<" den yparxei ston pinaka"<<endl;          
   // average 
   sumA=0;    
   for (i=0; i<N; i++) sumA +=A[i];
   m=(double) sumA/N;
   cout<<"O MESOS OROS TWN Ai EINAI -> "<<m<<endl;
   // stabdard deviation 
   sumA2=0;    
   for (i=0; i<N; i++) sumA2=sumA2+pow(A[i]-m, 2);
   s=sqrt(sumA2/N);
   cout<<"H TYPIKH APOKLISH TWN Ai EINAI -> "<<s<<endl;  
    
   system("PAUSE");
   return 0;     
}