1、#include "PRO.h"//程序目录的相对路悄钸碌灵径中的头文件.#include <iostream>//输入输出头文件.
![C++程序代码解析:[10]函数声明](https://exp-picture.cdn.bcebos.com/32a127723d03bbeab72707fcea43d7d449315435.jpg)
2、using namespace std;//所有标识符都被定义于一个名为std的namespace中.
![C++程序代码解析:[10]函数声明](https://exp-picture.cdn.bcebos.com/49701aebf6a75f0f138a435a97324b18502c4c35.jpg)
3、int main()//主函数
![C++程序代码解析:[10]函数声明](https://exp-picture.cdn.bcebos.com/d9e638334884cde3d08d615af07f860e7d754235.jpg)
4、float add(float x,float y);//对add函数作声明
![C++程序代码解析:[10]函数声明](https://exp-picture.cdn.bcebos.com/3b8fb4d7726b0ce2c24603bbef781423bfb9b635.jpg)
5、float a巳呀屋饔,b,c;cout <<"please enter a,b:";//输出cin >>a >>b;//输入a,bc=a颊俄岿髭dd(a,b);//调用函数cout <<"sum=" <<c <<endl;
![C++程序代码解析:[10]函数声明](https://exp-picture.cdn.bcebos.com/ba97ffd06de89a613484762745e8b004551bad35.jpg)
6、float a蟠校盯昂dd(float x, float y)//定义add函数{float z;z=x+y;return(z);}
![C++程序代码解析:[10]函数声明](https://exp-picture.cdn.bcebos.com/f367139a310e1799558b8d0cc9406afec214a335.jpg)
7、程序完整源码如下:
![C++程序代码解析:[10]函数声明](https://exp-picture.cdn.bcebos.com/f0848bee41c1b72769f2313c1a2ca5cadde89835.jpg)
8、程序运行结果如下:
![C++程序代码解析:[10]函数声明](https://exp-picture.cdn.bcebos.com/91091efc77f7980e918174c5d4db3620b83a9135.jpg)