number_guessing_game.c

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

const int MIN = 1;    // The minimum value for the guessing range
const int MAX = 100;  // The maximum value for the guessing range

int guess;            // The user's current guess
int tries;            // The number of attempts the user has made
int answer;           // The randomly generated correct answer
int lastGuess;        // The user's last guess

// Function to generate a random number within a specified range
int randomNumber(int lower, int upper)
{
    srand(time(0));   // Seed the random number generator with the current time
    return (rand() % (upper - lower + 1)) + lower;
}

// Function to check if a string input represents a valid integer
int isInteger(char input[])
{
    for (int i = 0; input[i] != '\0'; i++)
    {
        if (input[i] < '0' || input[i] > '9')
        {
            return 0; // Not a valid integer
        }
    }
    return 1; // Valid integer
}

int main()
{
    // Generate a random number and initialize variables
    answer = randomNumber(MIN, MAX);
    printf("Welcome to the Number Guessing Game!\n");

    do
    {
        char input[8]; // Buffer to store user input

        printf("Enter your guess (%d-%d): ", MIN, MAX);
        scanf("%s", input);

        // Check if the input is a valid integer
        if (!isInteger(input) || atoi(input) > MAX)
        {
            printf("Please enter a valid number between %d and %d.\n", MIN, MAX);
            tries++;
            continue;
        }

        guess = atoi(input); // Convert the valid input to an integer

        if (guess < answer)
        {
            printf("Guess higher!\n");
            tries++;
        }
        else if (guess > answer)
        {
            printf("Guess lower!\n");
            tries++;
        }

        lastGuess = guess;
    } while (guess != answer);

    // Display a congratulatory message and the number of tries
    printf("Congratulations! You guessed the correct number: %d\n", answer);

    if (tries == 1) {
        printf("You tried: %d time, and got it on the %d try\n", tries, tries + 1);
    }
    else {
        printf("You tried: %d times, and got it on the %d try\n", tries, tries + 1);
    }

    return 0;
}