C Exercises: Calculate body mass index and display the grade

Last update on March 18 2025 13:30:03 (UTC/GMT +8 hours)

Calculate BMI and display the category

Write a C program to calculate body mass index and display the grade from the following grades:
Underweight - BMI < 18.5
Normal weight - 18.5 <= BMI < 25.0
Overweight - 25.0 <= BMI < 30.0
Obesity - 30.0 <= BMI
Where weight is taken in kilograms and height in meters.
Body Mass Index (or BMI) is calculated as your weight (in kilograms) divided by the square of your height (in metres) or BMI = Kg/M².

Sample Solution:

C Code:

#include <stdio.h>

// Function to calculate and display BMI
void BMI(int, float);

int main(void) {
int w; // Variable to store weight
float h; // Variable to store height

    // Prompt user for weight and height
printf("Input the weight: ");
scanf("%d", &w);
printf("Input the height: ");
scanf("%f", &h);

    // Call the BMI function with provided weight and height
BMI(w, h);
}

// Function to calculate and display BMI
void BMI(int weight, float height) {
    // Calculate BMI using the provided formula
float temp = weight / (height * height);

    // Display the calculated BMI
printf("BMI = %f\n", temp);
printf("\nGrade: ");

    // Determine BMI grade and display it
temp< 18.5 ? printf("Under ") : temp < 25 ? printf("Normal ") : temp < 30 ? printf("Over ") : temp < 40 ? printf("Obese ") : printf("Error");
}

Sample Output:

Input the weight: 65
Input the height: 5.6
BMI = 2.072704

Grade: Under

Flowchart:

For more Practice: Solve these Related Problems:

Write a C program to calculate BMI given weight and height, and determine the corresponding health category.
Write a C program to compute BMI and display a detailed message based on BMI thresholds using if-else statements.
Write a C program to calculate BMI while handling edge cases such as zero or negative inputs.
Write a C program to compute BMI and classify it into underweight, normal, overweight, or obese categories.

C programming Code Editor:

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