c - 在 C 中显示最大值和最小值

Question

我在显示最低平均值时遇到问题。我做了一个终止值来结束考试分数的输入。当我触发 -999 并显示最低考试分数时，我收到的是 -999 的值，而不是实际的最低分数。我如何排除这个值？

这是我的代码:

#include <stdio.h>
#include <stdlib.h>
#include <math.h>

int main()
{
    int menuChoice, scoreCount = 0;
    float examScore = 0.0, 
          maxScore = 0.0,
          minScore = 0.0, 
          avgScore = 0.0, 
          sumScore = 0.0;

    printf("************************************\n");
    printf("1-> Enter an Exam Score\n");
    printf("2-> Display the highest exam score\n");
    printf("3-> Display the lowest exam score\n");
    printf("4-> Display the average exam score\n");
    printf("5-> Quit the program\n");
    printf("************************************\n\n");

    printf("Select a number that corresponds to the menu :\n");
    scanf("%d", &menuChoice);

    while(menuChoice != 5) 
    {
        switch(menuChoice)
        {
        case 1:
            while(examScore != -999)
            {
                printf("Enter an exam score (enter -999 to quit score input):\n");
                scanf("%f", &examScore);
                printf("The score you've entered equates to : %.2f\n\n", examScore);
                scoreCount++;

                if(maxScore < examScore)
                {
                    maxScore = examScore;
                }
                if(minScore > examScore)
                {
                    minScore = examScore;
                }
                else if(examScore < 0 || examScore > 100)
                {
                  printf("Exam Scores range from 0.0 - 100.0\n");
                }
                sumScore += examScore;
                avgScore = sumScore / scoreCount;
            }
            break;

        case 2:
            printf("The highest exam score is : %.2f\n", maxScore);
            break;

        case 3:
            printf("The lowest exam score is : %.2f\n", minScore);
            break;

        case 4:
            printf("The average exam score is : %.2f", avgScore);              
            break;

        default:
            printf("You've entered an invalid menu choice, review more carefully!");
            break;
        }

        printf("Select a number that corresponds to the menu :\n");
        scanf("%d", &menuChoice);
    } 

    system("pause");
    return 0;
}

Answer 1

修复 while 循环的逻辑。你更新minScore在查看是否examScore之前是-999，所以这不好。

您还应该初始化变量，例如 examScore在使用它们之前，您不应该像 examScore != -999 这样进行精确比较与花车。要么更改为整数，要么进行更宽容的比较，例如 examScore < -998 .