int permutare ( int a[] , int n )
{
 short v[1005] = {0} ;
 for ( int i = 0 ; i < n ; ++i )
     ++v[a[i]] ;
 int var = 1 ;
 for ( int i = 0 ; i < n ; ++i )
         if ( a[i] == i + 1 ) var = 0 ;
 for ( int i = 1 ; i <= n && var ; ++i )
      if ( v[i] == 0 ) var = 0 ;
        else if  ( v[i] > 1 ) var = 0 ;
 if ( var ) return 1 ;
   else return 0 ;
}