Îļþ¶ÁÈëÎÊÌâ

°¢Âê±ÈÀ×

ÕâÊÇÎÒѧϰÎļþ¶ÁÈëʱдµÄÒ»¸ö³ÌÐò,Çë´ó¼Ò°ï¸öæ,Ϊʲô×ÜÊÇÉÙ¶ÁÒ»¸öÊý×ÖÄØ?¶àлָµã.

#include <iostream>
#include <fstream>
#include <cstdlib>
using namespace std;

const int SIZE = 60;
int main()
{
    char fileName[SIZE];
    ifstream inFile;
   
    cout << "Please enter the file name:";
    cin.getline(fileName,SIZE);
    inFile.open(fileName);
    if(!inFile.is_open())
    {
        cout << "Sorry! This file can't open ."
             << "Program terminating.";
        exit(EXIT_FAILURE);
    }
    double value;
    double sum=0;
    int count=0;

    inFile >> value;
    while(inFile.good())
    {
        ++count;
        sum += value;
        inFile >> value;
    }
    if(inFile.eof())
        cout << "It's the end of the file.\n";
    else if(inFile.fail())
        cout << "Input terminated by data mismatch.\n";
    else
        cout << "Input terminated by unknown reason.\n";
   
    if(0 == count)
        cout << "No data processed.\n";
    else
    {
        cout << "Items read:" << count << endl;
        cout << "Sum:" << sum << endl;
        cout << "Average:" << sum/count << endl;
    }
    inFile.close();

   
    return 0;
}

º£µÄÎÞÄÎ

³ÌÐò´úÂ룺
#include <iostream>
#include <fstream>
#include <cstdlib>
using namespace std;

const int SIZE = 60;
int main()
{
    char fileName[SIZE];
    ifstream inFile;
   
    cout << "Please enter the file name:";
    cin.getline(fileName,SIZE);
    inFile.open(fileName);
    if(!inFile.is_open())
    {
        cout << "Sorry! This file can't open ."
             << "Program terminating.";
        exit(EXIT_FAILURE);
    }
    double value;
    double sum=0;
    int count=0;

    //inFile>>value;Õâ¸öҪȥµô£¬ÒòΪÔËÐÐÁËÕâ¸öºó£¬ÎļþÖ¸ÕëÒѾ­Ö¸ÏòÁ˺óÃ棬ÄãÊÔ×ÅÖ»·ÖÎö3¸öÊý¾Ý¾Í»áÃ÷°×µÄ
    while(inFile.good())
    {   inFile >> value;
        ++count;
        sum += value;
        
    }
    if(inFile.eof())
        cout << "It's the end of the file.\n";
    else if(inFile.fail())
        cout << "Input terminated by data mismatch.\n";
    else
        cout << "Input terminated by unknown reason.\n";
   
    if(0 == count)
        cout << "No data processed.\n";
    else
    {
        cout << "Items read:" << count << endl;
        cout << "Sum:" << sum << endl;
        cout << "Average:" << sum/count << endl;
    }
    inFile.close();

   
    return 0;
}

ºì³¾×í

ÎļþÖÐÊý¾ÝÈçÏÂ:
18 19 18.5 13.5 14
16 19.5 20 18 12 18.5