// for.cc   examples of scope rules  (this is one file)
// SGI  CC -n32 -LANG:ansi-for-init-scope=ON for.cc
//          an old version of C++ will give error on second for(int i=0; ...
//          an old version of C++ will give error on second s=7 

#include <iostream.h> // should be #include <iostream>

int funct(int s=7); // just a function prototype
                    // prototype visible in this file
                    // binary visible to everything linked

int k = 1;   // this is global to everything linked

int main()   // visible to linker, only one 'main' allowed per link
{
    int j=0;   // this is global to this file

    for(int i=0; i<10; i++)  // 'i' declared and defined inside loop
    {
       j=j+i;                // this is a local 'i'
    }
    cout << "j=" << j << " k=" << k << endl; // can not print 'i' here

    // int j=3; // not legal, redeclaration of 'j'
    int i=2;    // should be OK, scope of i is just loop
    j = 3;
    k = 3;

    for(int i=1; i<5; i++)
    {
       j=j+k+i;              // this is another 'i' local to this loop
    }
    cout << "j=" << j << "  k=" << k << "  i=" << i << endl;
                                    // can print 'i' before loop here

    j = funct();
    cout << "j using default=" << j << endl;

    j = funct(5);
    cout << "j using funct(5)=" << j << endl; 

    return 0; 
  }

       //          =7  should be allowed
int funct(int s /* =7 */ ) // if no value for 's' then, use '7' as default
{
    // j=5; // no. 'j' only visible inside 'main' above
    bool b;    // check for type defined
    b = true;
    b = false; // check for enumeration literals defined

    k=7;    // OK, global
    cout << "k=" << k << "  b=" << b << endl;

    return s+k;
}

//             Result of running this program
// j=45 k=1
// j=25  k=3  i=2
// k=7  b=0
// j using default=14
// k=7  b=0
// j using funct(5)=12