Thread: Break from a for loop with a flag. - Game get at least 3 numbers from 6

I don´t understand why my program fail, when i try to jump out of a loop using a flag.

Code:

        int flag = 0;


        for (int i = 0; i < KEY_SIZE; i++) {
            for (int j = 0; j < KEY_SIZE || flag == 1; j++) {
                if (key[i] == keyinput[j]) {
                    jackpot++;
                    flag = 1;
                }
            }
            flag = 0;
        }

If i do with a break everything works ok

Code:

        for (int i = 0; i < KEY_SIZE; i++) {
            for (int j = 0; j < KEY_SIZE; j++) {
                if (key[i] == keyinput[j]) {
                    jackpot++;
                    break;
                }
            }
        }

The full code is here.

If you got more then 2 numbers on a key you are a winner.

Text file(keys.txt)
6 7 8 9 40 45
8 9 33 34 36 41
1 2 3 4 5 8

Code:

#include <stdio.h>
#include <stdlib.h>
#define SIZE 100
#define KEY_SIZE 6


int main(int argc, char** argv) {


    FILE *pFile;


    int keyinput[KEY_SIZE] = {2, 3, 4, 5, 6, 7};
    int key[KEY_SIZE];
    char buffer[SIZE];
    int jackpot = 0;


    if ((pFile = fopen(argv[1], "r")) == NULL) {
        return -1;
    }


    while (fgets(buffer, sizeof (buffer), pFile)) {
        sscanf(buffer, "%d %d %d %d %d %d", &key[0], &key[1], &key[2], &key[3], &key[4], &key[5]);


        int flag = 0;


        for (int i = 0; i < KEY_SIZE; i++) {
            for (int j = 0; j < KEY_SIZE; j++) {
                if (key[i] == keyinput[j]) {
                    jackpot++;
                    break;
                }
            }
            flag = 0;
        }


        if (jackpot >= 3) {
            puts("That key is a winner");
        } else {
            jackpot = 0;
        }
    }


    return (EXIT_SUCCESS);
}

I think you can use the for loop to break as you want if the middle part is like this:

j < KEY_SIZE && flag == 0

I could be wrong but that seems right to me.

Originally Posted by BpB

I think you can use the for loop to break as you want if the middle part is like this:

j < KEY_SIZE && flag == 0

I could be wrong but that seems right to me.

Yes i was messing with || and &&

Code:

 for (int j = 0; j < KEY_SIZE || flag == 0; j++)

it works

Code:

   int flag = 0;

    for (int i = 0; i < KEY_SIZE; i++) {
            for (int j = 0; j < KEY_SIZE && flag == 0; j++) {
                 if (key[i] == keyinput[j]) {
                    jackpot++;
                    flag = 1;
                }
            }
            flag = 0;
        }