Srećan broj

#include <iostream>
#include <cmath>
using namespace std;

int  suma (int a)
{
     int k=0;

     while (a>0)
     {
           k = k + (a%10)*(a%10);
           a = a / 10;
     }

     return k;
}

bool srecan (int n)
{
      bool p = false;
      int t, s, i;

      t = suma(n);
      if (t==1)
      p = true;

      s = t;
      i = n;

      do
      {
            s = suma(s);
            if (s==1)
            p = true;
            i = i - 1;
      }
      while ((s!=t)&&(s!=1)&&(i>0));

      return p;
}

main()
{
      int n, x = 0, i;

      cin >> n;

      i = n - 1;

      while ((i>0)&&(x==0))
      {
            if (srecan (i) == true)
            x = i;
            i = i - 1;
      }

      cout << x << endl;

      system ("PAUSE");
}