Random Number Memory Game in C

// C program to implements the above
// memory game
#include <conio.h>
#include <dos.h>
#include <stdio.h>
#include <stdlib.h>

// Function to generate the random
// number at each new level
int randomnum(long level)
{
    clrscr();
    printf("Level %ld \n", level);

    long num;
    num = (rand() % 100 * level)
          + 1 + level * 5.2f;

    printf("Number : %ld \n", num);
    delay(2000 - (10 * level));
    clrscr();

    // Return the number
    return num;
}

// Driver Code
void main()
{
    clrscr();
    long num;
    long guessnum;

    long level = 1;

    long inputnum;

    // Start the game
    printf("Press 1 to start Game! ");
    scanf("%ld", &inputnum);

    // Game Starts
    if (inputnum == 1) {

        // Iterate until game ends
        do {

            // Generate a random number
            num = randomnum(level);

            // Get the guessed number
            scanf("%ld", &guessnum);
            level++;

            // Condition for the Game
            // Over State
            if (guessnum != num) {
                printf("You Failed! ");
            }
        } while (num == guessnum);
    }

    getch();
}