C (Basic stuff) - 将用户输入写入文件

Question

基本上，我想让用户在一个文本文件（2 列）中输入四个姓名和四个等级；举个例子：

98 年 3 月

迈克 60

约翰 78

贝丝 89

我希望能够读取文件（可能使用 fscanf）并显示最高/最低等级，以及它们的平均值。所以我需要为所有输入创建变量，对吧？今天在课堂上，我们学习了结构，所以我假设可能需要实现一个。我没有真正有用的代码，但这是它的开始：

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.
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int main()
{

int i;

FILE *Fpointer;
char input[100];
int input2[4];


Fpointer = fopen("file.txt", "w");

for(i = 0; i < 4; i++)
{
    printf("Enter a name>");
    scanf("%s", input);
    printf("Enter a grade>");
    // User Josh Bressers told me to change the below %d to %s
    scanf("%s", input2);
    // And the second %d to %s here
    // The program prints 4 names and 4 numbers perfectly now
    fprintf(Fpointer, "%s %s", input, input2);
    fprintf(Fpointer, "\n");

}

fclose(Fpointer);

return 0;


}

既然程序接受了用户输入的四个姓名和数字，我将如何读取数字并进行第一段中列出的计算？任何帮助表示赞赏！

谢谢，

TP

编辑：我自己搞定了（丑陋，但它有效）

Answer 1

将 input2 读取为字符串，而不是整数。您可以通过 atoi() 字符串来获取整数，也可以通过将 %d 更改为 %s 将其写为字符串。

Answer 2

我自己弄的……

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


// Name of file to be created and data saved in
#define FILENAME "students_and_grades.txt"
// Size of arrays for names
#define NAME_ARRAY_SIZE 25


// Declare arrays
char arrcName1[NAME_ARRAY_SIZE];
char arrcName2[NAME_ARRAY_SIZE];
char arrcName3[NAME_ARRAY_SIZE];
char arrcName4[NAME_ARRAY_SIZE];
char arrcHighestName[NAME_ARRAY_SIZE];
char arrcLowestName[NAME_ARRAY_SIZE];


int main()
{
printf("----Tyler Procko----\n\n\n");

//Declare
int iScore1, iScore2, iScore3, iScore4;
int iHighestScore, iLowestScore;
double dScoreAverage;

// Declare file pointer
FILE *Fpointer;

// Open file for writing
Fpointer = fopen(FILENAME, "w");


// Ask user for first student name and score
printf("What is the first student's name?   ");
scanf("%s", arrcName1);

// Check range (0-100)
do
{
    printf("What is the first student's grade?   ");
    scanf("%d", &iScore1);

} while ((iScore1 < 0) || (iScore1 > 100));


// Ask user for second student name and score
printf("What is the second student's name?   ");
scanf("%s", arrcName2);

// Check range (0-100)
do
{
    printf("What is the second student's grade?   ");
    scanf("%d", &iScore2);

} while ((iScore2 < 0) || (iScore2 > 100));


// Ask user for third student name and score
printf("What is the third student's name?   ");
scanf("%s", arrcName3);

// Check range (0-100)
do
{
    printf("What is the third student's grade?   ");
    scanf("%d", &iScore3);

} while ((iScore3 < 0) || (iScore3 > 100));


// Ask user for fourth student name and score
printf("What is the fourth student's name?   ");
scanf("%s", arrcName4);

// Check range (0-100)
do
{
    printf("What is the fourth student's grade?   ");
    scanf("%d", &iScore4);

} while ((iScore4 < 0) || (iScore4 > 100));


// Print student name's and grades to file
fprintf(Fpointer, "%s %d\n", arrcName1, iScore1);
fprintf(Fpointer, "%s %d\n", arrcName2, iScore2);
fprintf(Fpointer, "%s %d\n", arrcName3, iScore3);
fprintf(Fpointer, "%s %d\n", arrcName4, iScore4);

// Close file
fclose(Fpointer);


// Open file for reading
Fpointer = fopen(FILENAME, "r");


// If file is there and working properly, scan it
if (Fpointer != NULL)
{
// Scan file for data
fscanf(Fpointer, "%s %d", arrcName1, &iScore1);
fscanf(Fpointer, "%s %d", arrcName2, &iScore2);
fscanf(Fpointer, "%s %d", arrcName3, &iScore3);
fscanf(Fpointer, "%s %d", arrcName4, &iScore4);

}

// Otherwise, ERROR
else
{
    printf("ERROR: File not found!");

}

// Display it all, just for the visual
printf("\nStudent one, %s, scored a %d.\n", arrcName1, iScore1);
printf("Student two, %s, scored a %d.\n", arrcName2, iScore2);
printf("Student three, %s, scored a %d.\n", arrcName3, iScore3);
printf("Student four, %s, scored a %d.\n\n", arrcName4, iScore4);


// Assume the first is the highest
iHighestScore = iScore1;
strcpy(arrcHighestName, arrcName1);

// Assume the first is the lowest
iLowestScore = iScore1;
strcpy(arrcLowestName, arrcName1);

// Compare score 2 to score 1
// Highest
if (iScore2 > iScore1)
{
    iHighestScore = iScore2;
    strcpy(arrcHighestName, arrcName2);

}

// Lowest
if (iScore2 < iScore1)
{
    iLowestScore = iScore2;
    strcpy(arrcLowestName, arrcName2);

}

// Compare score 3 to score 2 and 1
// Highest
if ((iScore3 > iScore2) && (iScore3 > iScore1))
{
    iHighestScore = iScore3;
    strcpy(arrcHighestName, arrcName3);

}

// Lowest
 if ((iScore3 < iScore2) && (iScore3 < iScore1))
{
    iLowestScore = iScore3;
    strcpy(arrcLowestName, arrcName3);

}

// Compare score 4 to score 3, 2 and 1
// Highest
if ((iScore4 > iScore3) && (iScore4 > iScore2) && (iScore4 > iScore1))
{
    iHighestScore = iScore4;
    strcpy(arrcHighestName, arrcName4);

}

// Lowest
 if ((iScore4 < iScore3) && (iScore4 < iScore2) && (iScore4 < iScore1))
{
    iLowestScore = iScore4;
    strcpy(arrcLowestName, arrcName4);

}

// Print highest and lowest scores and their respective students
printf("\nThe highest score was a %d from %s.\n", iHighestScore,               
arrcHighestName);
printf("The lowest score was a %d from %s.\n", iLowestScore, 
arrcLowestName);


// Perform average calculation and print result
dScoreAverage = (iScore1 + iScore2 + iScore3 + iScore4) / 4.0;
printf("\n\nThe test average is %.2f\n\n", dScoreAverage);


// Close file
fclose(Fpointer);

return 0;