C Exercises: Calculate the sum of three numbers getting input in one line

Last update on March 18 2025 13:36:34 (UTC/GMT +8 hours)

8. Sum of Three Numbers

Write a program in C to calculate the sum of three numbers with input on one line separated by a comma.

Pictorial Presentation:

Sample Solution:

C Code:

#include <stdio.h>     // Include the standard input/output header file.

int num1, num2, num3;   /* declaration of three variables */  
int sum;                /* variable to store the sum of numbers */
char line_text[50];     /* line of input from keyboard */ 

int main() 
{  
printf("Input three numbers separated by comma : ");   // Prompt the user to input three numbers separated by comma.
fgets(line_text, sizeof(line_text), stdin);   // Read a line of input from the user and store it in 'line_text'.
sscanf(line_text, "%d, %d, %d", &num1, &num2, &num3);   // Convert the input to integers and store them in 'num1', 'num2', 'num3'.
sum = num1 + num2 + num3;   // Calculate the sum of the three numbers.
printf("The sum of three numbers : %d\n", sum);   // Print the sum of the three numbers.  
return(0);   // Return 0 to indicate successful execution of the program.  
}  

Sample Output:

Input three numbers seperated by comma : 5,10,15                                                              
The sum of three numbers : 30 

Flowchart:

For more Practice: Solve these Related Problems:

• Write a C program to parse three comma-separated numbers from a single input line and calculate their product instead of the sum.
• Write a C program to compute the sum of three numbers provided in one line and then calculate their average.
• Write a C program to sum three comma-separated numbers and detect any non-numeric input, prompting for re-entry.
• Write a C program to sum three numbers provided on one line and then display them in ascending order.

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