c - BMI 计算器实验室找不到问题

Question

对于这个实验，我不允许编辑 main 函数，所有事情都必须在 main 下面的函数中完成。我在这里似乎找不到我的问题。我认为这与调用calculateBMI函数有关。

 #include <stdio.h>
    FILE *fp;

    //For loop, which allows up to 4 entries.
    int main(void) {
        int i;

        fp = fopen("csis.txt", "w");
        for (i = 1; i <= 4; ++i) {
            calculateBMI();
        }
        fclose(fp);
        return 0;
    }

    //Function that calculates the BMI of the Input.
    double calculateBMI(int weightInPounds, int heightInInches) {
        double BMI;

        BMI = weightInPounds * 703 / heightInInches * heightInInches;

        //If BMi is less then 18.5 print this.
        if (BMI < 18.5) {
            printf("Your BMI is %d, you are underweight.", BMI);
            fprintf(fp, "Your BMI is %d, you are underweight.", BMI);
        }
        //if BMI is between 18.5 and less then 25 print this.
        else if (BMI > 18.5 & BMI < 25) {
            printf("Your BMI is %d, you are Normal.", BMI);
            fprintf(fp, "Your BMI is %d, you are Normal.", BMI);
        }
        //if BMI is greater then 25 and less then 30 print this.
        else if (BMI > 25 & BMI < 30) {
            printf("Your BMI is %d, you are Overweight.", BMI);
            fprintf(fp, "Your BMI is %d, you are Overweight.", BMI);
        }
        //if BMI is greater then 30 print this.
        else (BMI > 30) {
            printf("Your BMI is %d, you are Obese.", BMI);
            fprintf(fp, "Your BMI is %d, you are Obese.", BMI);
        }

        //Asks user for input weight in pounds.
        printf("What is your weight in pounds?");
        fprintf(fp, "What is your weight in pounds?");
        scanf("%d\n", weightInPounds);
        fscanf(fp, "%d\n", weightInPounds);

        // Asks user for input height in inches.
        printf("What is your height in inches?");
        fprintf("What is your height in inches?");
        scanf("%d\n", heightInInches);
        fscanf(fp, "%d\n", heightInInches);

        getchar(0);
        return (0);
    }

Answer 1

在 else if 语句中您使用了 & 运算符，但在本例中您需要使用 && 运算符。 & 运算符是按位运算符。例如，如果您有两个 4 位变量 1001 和 1010 。您使用 & 运算符，结果将是 1000 。在这种情况下，您必须使用 && 运算符它应该看起来像这样:

    else if (BMI > 18.5 && BMI < 25)