C Program: Guess the number game using while loop

Last update on December 20 2024 13:22:32 (UTC/GMT +8 hours)

Write a C program that generates a random number between 1 and 20 and asks the user to guess it. Use a while loop to give the user multiple chances until they guess the correct number.

Sample Solution:

C Code:

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

int main() {
    srand(time(NULL));  // Seed the random number generator with the current time
    int targetNumber = rand() % 20 + 1;  // Generate a random number between 1 and 20

    int userGuess;  // Variable to store the user's guess
    int attempts = 0;  // Variable to count the number of attempts

    printf("Guess the number between 1 and 20:\n");

    // Start a while loop to give the user multiple chances
    while (1) {
        printf("Input your guess: ");
        scanf("%d", &userGuess);  // Read the user's guess

        attempts++;  // Increment the number of attempts

        // Check if the guess is correct
        if (userGuess == targetNumber) {
            printf("Congratulations! You guessed the correct number in %d attempts.\n", attempts);
            break;  // Exit the loop if the guess is correct
        } else {
            printf("Incorrect guess. Try again!\n");
        }
    }

    return 0;  // Indicate successful program execution
}

Sample Output:

Guess the number between 1 and 20:
Input your guess: 20
Incorrect guess. Try again!
Input your guess: 11
Incorrect guess. Try again!
Input your guess: 12
Incorrect guess. Try again!
Input your guess: 13
Incorrect guess. Try again!
Input your guess: 17
Incorrect guess. Try again!
Input your guess: 18
Incorrect guess. Try again!
Input your guess: 19
Incorrect guess. Try again!
Input your guess: 14
Incorrect guess. Try again!
Input your guess: 1
Incorrect guess. Try again!
Input your guess: 2
Incorrect guess. Try again!
Input your guess: 5
Incorrect guess. Try again!
Input your guess: 3
Incorrect guess. Try again!
Input your guess: 7
Incorrect guess. Try again!
Input your guess: 8
Incorrect guess. Try again!
Input your guess: 6
Incorrect guess. Try again!
Input your guess: 9
Incorrect guess. Try again!
Input your guess: 10
Incorrect guess. Try again!
Input your guess: 11
Incorrect guess. Try again!
Input your guess: 12
Incorrect guess. Try again!
Input your guess: 13
Incorrect guess. Try again!
Input your guess: 14
Incorrect guess. Try again!
Input your guess: 15
Incorrect guess. Try again!
Input your guess: 16
Congratulations! You guessed the correct number in 23 attempts.

Explanation:

Here are key parts of the above code step by step:

#include <stdio.h>, #include <stdlib.h>, #include <time.h>: These lines provide necessary header files for standard input/output, random number generation, and time functions.
srand(time(NULL));: Seeds the random number generator using the current time.
int targetNumber = rand() % 20 + 1;: Generates a random number between 1 and 20 using rand() and the modulo operator. The result is stored in 'targetNumber'.
int userGuess;, int attempts = 0;: Declares variables to store the user's guess (userGuess) and the number of attempts made (attempts).
printf("Guess the number between 1 and 20:\n");: Prints a message prompting the user to guess a number between 1 and 20.
while (1) {: Starts an infinite while loop to give the user multiple chances. The loop will exit when the user guesses the correct number.
printf("Enter your guess: ");, scanf("%d", &userGuess);: Prompts the user to input their guess and reads the input as an integer.
attempts++;: Increments the attempts counter to keep track of the number of attempts.
if (userGuess == targetNumber) { ... }: Checks if the user's guess is equal to the randomly generated target number.
printf("Congratulations! You guessed the correct number in %d attempts.\n", attempts);: Prints a message along with the number of attempts if the guess is correct.
break;: Exits the loop if the user's guess is correct.
else { printf("Incorrect guess. Try again!\n"); }: Prints an error message if the user's guess is incorrect.
return 0;: Indicates successful program execution.
}: Closes the infinite "while" loop.
}: Closes the "main()" function.

Flowchart:

C Programming Code Editor:

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