why the score1 and score2 variables exceed the maximum value of 50?

Hello,

I have made this little game using the random function.
But there's a problem because the score1 and score2 exceeds the value of 50 contained in the while cycle.
I would like to understand why.

Thanks in advance...

Code:

---

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

int main(void)
{
        int dice1, dice2, score1, score2;
        srand((unsigned)time(NULL));

        dice1 = dice2 = score1 = score2 = 0;

        while(score1 < 50 || score2 < 50)
        {       
                //player 1
                dice1 = (rand()%6)+1;
                dice2 = (rand()%6)+1;
               
                if(dice1 == dice2)
                {
                        printf("Player 1 scored double %d\n", dice1);
                        if(dice1 == 3)
                                score1 = 0;
                        else if(dice1 == 6)
                                score1 = score1 + 25;
                        else
                                score1 = score1 + 5;
                        printf("Player 1 = %d\n", score1);
                }
               
                //player 2
                dice1 = (rand()%6)+1;
                dice2 = (rand()%6)+1;
                if(dice1 == dice2)
                {
                        printf("Player 2 scored double %d\n", dice1);
                        if(dice2 == 3)
                                score2 = 0;
                        else if(dice2 == 6)
                                score2 = score2 + 25;
                        else
                                score2 = score2 + 5;
                        printf("Player 2 = %d\n", score2);
                }
        }
        if(score1 == score2)
                printf("Game is a tie\n");
        else if(score1 < score2)
                printf("Player 1 Wins\n");
        else
                printf("Player 2 Wins\n");

        return 0;
}

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Code:

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score1 < 50 || score2 < 50

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will be true if score1 or score2 is less than 50 - so it will continue until BOTH are 50 or more.

--
Mats

Quote:

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Originally Posted by matsp

Code:

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score1 < 50 || score2 < 50

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will be true if score1 or score2 is less than 50 - so it will continue until BOTH are 50 or more.

--
Mats

---

I tried with && and it still continues over the limit. There's something I can't understand. =P

The loop exits when ONE value is over 50 (when using &&). If you do not want to add a value to exceed 50, then you need to check BEFORE you add if it's breaking the limit or not.

--
Mats

Quote:

---

Originally Posted by matsp

The loop exits when ONE value is over 50 (when using &&). If you do not want to add a value to exceed 50, then you need to check BEFORE you add if it's breaking the limit or not.

--
Mats

---

so I should use that construct called DO ... WHILE which I haven't studied yet! =P

Quote:

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Originally Posted by fsx

so I should use that construct called DO ... WHILE which I haven't studied yet! =P

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I just compiled and tested the OP using "&&" and it does not go over the limit. Perhaps you made some other change afterward; anyway, if you change || to && it will work the way you intend.

Quote:

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Originally Posted by fsx

so I should use that construct called DO ... WHILE which I haven't studied yet! =P

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Makes little difference, I expect.

You need to check BEFORE the add if the sum is going to be too large.

--
Mats

Hello.

Quote:

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Originally Posted by MK27

I just compiled and tested the OP using "&&" and it does not go over the limit. Perhaps you made some other change afterward; anyway, if you change || to && it will work the way you intend.

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Actually, this depends. For example, if score1 is 45 before the last dice throw and you get two 6, the final score will be 70.

Quote:

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Originally Posted by tadeboro

Hello.
Actually, this depends. For example, if score1 is 45 before the last dice throw and you get two 6, the final score will be 70.

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Okay. This would seem a slightly different issue (from the one whereby no one could win until both players top 50).

Quote:

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Originally Posted by tadeboro

Hello.
Actually, this depends. For example, if score1 is 45 before the last dice throw and you get two 6, the final score will be 70.

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And to solve that, you need to add a check that validates the total value is still under 51 - or say "bust" or whatever.

--
Mats

Quote:

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Originally Posted by matsp

And to solve that, you need to add a check that validates the total value is still under 51 - or say "bust" or whatever.

--
Mats

---

I have added

Code:

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                if(score1 >= 50 || score2 >= 50)
                        break;

---

after the while, but it stills won't work. Probably I should rework it completely. Is there a way to reuse my code?

I don't know exactly what you the rules for the game is. But if we assume that the rules are "if the sum gets above 50, no score", then something like this:

Code:

---

int throwscore = 0;
...
if (dice1 == dice2)
{
  ...
  if (dice1 == 6)
      throw_score = 25;
  else
      throw_score = 5;
  if (score1 + throw_score <= 50)
      score1 += throw_score;
}

---

You may need to adjust this to match your actual scoring rules, but something like that.

--
Mats

Final run:

Code:

---

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

int main(void)
{
        int die1, die2, score1, score2, throwscore;
        srand((unsigned)time(NULL));

        die1 = die2 = score1 = score2 = throwscore = 0;

        while(score1 < 50 && score2 < 50)
        {       
                //player 1
                die1 = (rand()%6)+1;
                die2 = (rand()%6)+1;
               
                if(die1 == die2)
                {
                        printf("Player 1 scored double %d\n", die1);
                        if(die1 == 3)
                                throwscore = score1 = 0;
                        else if(die1 == 6)
                                throwscore = 25;
                        else
                                throwscore = 5;

                        if(score1 + throwscore <= 50)
                                score1 += throwscore;

                        printf("Player 1 = %d\n", score1);
                }
               
                //player 2
                die1 = (rand()%6)+1;
                die2 = (rand()%6)+1;
                if(die1 == die2)
                {
                        printf("Player 2 scored double %d\n", die1);
                        if(die1 == 3)
                                throwscore = score2 = 0;
                        else if(die2 == 6)
                                throwscore = 25;
                        else
                                throwscore = 5;

                        if(score2 + throwscore <= 50)
                                score2 += throwscore;

                        printf("Player 2 = %d\n", score2);
                }
        }
        if(score1 == score2)
                printf("Game is a tie\n");
        else if(score1 > score2)
                printf("Player 1 Wins\n");
        else
                printf("Player 2 Wins\n");

        return 0;
}

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It works! Thanks matsp, you cleared my ideas! =)