c++ - 如何正确显示文本文件中的最大数字？

Question

因此，对于我的作业，我需要读取一个包含学生姓名和考试成绩的文本文件，并在屏幕上显示平均考试成绩和最高考试成绩。

文本文件的内容是:

• 约翰·史密斯 99
• 莎拉·约翰逊 85 岁
• 吉姆罗宾逊 70
• 玛丽·安德森 100
• 迈克尔· jackson 92

我目前的代码是:

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

void inputFile(string, string, int, int, int, int);

int main()
{
    string firstName;
    string lastName;
    int testScore = 0;
    int totalScore = 0;
    int avgScore = 0;
    int highestScore = 0;

    inputFile(firstName, lastName, testScore, totalScore, avgScore, highestScore);

    system("pause");
    return 0;
}

void inputFile(string firstName, string lastName, int testScore, int totalScore, int avgScore, int highestScore)
{
    ifstream myFile("scores.txt");

    int i = 0;
    while (myFile >> firstName >> lastName >> testScore) {
        totalScore = totalScore + testScore;
        i++;
    }
    avgScore = totalScore / i;
    cout << "Average score: " << avgScore << endl;

    while (myFile >> firstName >> lastName >> testScore) {
        if (highestScore < testScore) {
            highestScore = testScore;
        }
    }
    cout << "Highest score: " << highestScore << endl;
}

当我运行该程序时，它会正确显示平均分，但当涉及到最高分时，它每次都只显示“0”，而不是显示文本文件中最大的数字“100”。我如何让它显示“highestScore”的“100”而不是“0”？

Answer 1

while (myFile >> firstName >> lastName >> testScore) {
    if (highestScore < testScore) {
        highestScore = testScore;
    }
}

为什么要再次尝试读取文件？你应该在总结的同时处理它:

while (myFile >> firstName >> lastName >> testScore) {
    totalScore = totalScore + testScore;
    if (highestScore < testScore) {
        highestScore = testScore;
    }
    i++;
}

或者，rewind the file在尝试再次阅读之前:

myfile.clear();
myfile.seekg(0);
while (myFile >> firstName >> lastName >> testScore) {
    /* stuff... */