C++ examples for Function:Global Variable
Demonstrating scope, lifetime, and global variables
#include <iostream> long count1 {999L}; // Global count1 double count2 {3.14}; // Global count2 int count3; // Global count3 - default intialization int main() {/*from w ww . j a va 2s. c o m*/ int count1 {10}; // Hides global count1 int count3 {50}; // Hides global count3 std::cout << "Value of outer count1 = " << count1 << std::endl; std::cout << "Value of global count1 = " << ::count1 << std::endl; std::cout << "Value of global count2 = " << count1 << std::endl; { // New block scope starts here... int count1 {20}; int count2 {30}; std::cout << "\nValue of inner count1 = " << count1 << std::endl; std::cout << "Value of global count1 = " << ::count1 << std::endl; std::cout << "Value of inner count2 = " << count2 << std::endl; std::cout << "Value of global count2 = " << ::count2 << std::endl; count1 = ::count1 + 3; ++::count1; std::cout << "\nValue of inner count1 = " << count1 << std::endl; std::cout << "Value of global count1 = " << ::count1 << std::endl; count3 += count2; } std::cout << "\nValue of outer count1 = " << count1 << std::endl << "Value of outer count3 = " << count3 << std::endl; std::cout << "Value of global count3 = " << ::count3 << std::endl; std::cout << count2 << std::endl; }