我的c函数返回乱码

Question

So basically whenever I input a grade it gives me back a random symbol, even though I have defined grade. Wouldn't it better if i used the value from return grade; but I don't know how to retrieve that character into my main function :<

#include <stdio.h>

char GradeFromPercentage(float percentage);

int main() {
    float percentage1;
    printf("Enter the student's percentage:");
    scanf("%f", &percentage1);
    printf("Student's grade is %c \n", GradeFromPercentage(percentage1));
    return 0;
}

char GradeFromPercentage(float percentage) {
    char grade;
    if (percentage >= 90) {
        grade = "A";
    } else
    if (percentage >= 70) {
        grade = "B";
    } else
    if (percentage >= 50) {
        grade = "C";
    } else
    if (percentage >= 30) {
        grade = "D";
    } else {
        grade = "F";
    }
    return grade;
}

Answer 1

Change the function GradeFromPercentage , you were assigning char* instead of char

char GradeFromPercentage(float percentage)
{

    char grade;
    if (percentage >= 90)
    {
        grade = 'A';
    }
    else if (percentage >= 70)
    {
        grade = 'B';
    }
    else if (percentage >= 50)
    {
        grade = 'C';
    }
    else if (percentage >= 30)
    {
        grade = 'D';
    }
    else
    {
        grade = 'F';
    }
    return grade;
}

Answer 2

You assign strings to a char variable in GradeFromPercentage() . You should use character constants with single quotes instead of character strings with double quotes.

Here is a corrected and simplified version:

char GradeFromPercentage(float percentage) {
    if (percentage >= 90) {
        return 'A';
    }
    if (percentage >= 70) {
        return 'B';
    }
    if (percentage >= 50) {
        return 'C';
    }
    if (percentage >= 30) {
        return 'D';
    }
    return 'F';
}