函数可变参数列表

古月不傲

[C++] 纯文本查看 复制代码

#include <iostream>
#include <cstdarg>

using namespace std;
/*
num: the num is number of arg that was passed from main().
*/
double sum(int num, ...)
{
    va_list arg;    // stores the list of arg
    
    double sum = 0;  
    va_start(arg, num);     // init the list

    for (int i = 0; i < num; i++) {
        sum += va_arg(arg, double); // return the next arg in the list
    }
    va_end(arg);    // clear the list

    return sum;
}

int main(void)
{
    cout << sum(5, 1.0, 5.5, 7.8, 3.6, 2.5) << endl;

    // Note that it's error as following.
    // cout << sum(5, 1.0, 5.5, 7.8, 3, 2) << endl;    // error    because it wasn't consistent with double type for 3 and 2.

    return 0;
}

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maqiao144

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