#include <iostream>
using namespace std;
int sum(int a, int b=20)
{
        int result;
        result = a + b;
        return (result);
}
int main ()
{
        int a = 100;
        int b = 200;
        int result;
        result = sum(a, b); cout << "Total value is :" << result << endl;
        result = sum(b); cout << "Total value is :" << result << endl; return 0;
}


第二个result的结果为什么是 220 ？
--
修改:rayren FROM 183.14.135.*
FROM 183.14.135.*