Building Teams

input/code.c: In function 'main':
input/code.c:6:5: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
    6 |     scanf("%d %d", &m, &n);
      |     ^~~~~~~~~~~~~~~~~~~~~~
input/code.c:14:9: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
   14 |         scanf("%d %d", pair1 + i, pair2 + i);
      |         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

#include <stdio.h>
#include <stdlib.h>
int main() {
    int n;
    int m;
    scanf("%d %d", &m, &n);
    int* pair1 = (int*)malloc(n * sizeof(int));
    int* pair2 = (int*)malloc(n * sizeof(int));
    int* team = (int*)malloc(m * sizeof(int));
    for (int i = 0; i < m; ++i) { *(team + i) = -1; }
    
    int impossible = 0;
    for (int i = 0; i < n; ++i) {
        scanf("%d %d", pair1 + i, pair2 + i);
        int p1 = (*(pair1 + i)) - 1;
        int p2 = (*(pair2 + i)) - 1;
        int t1 = *(team + p1);
        int t2 = *(team + p2);
        if (t1 == -1) {
            if (t2 == -1) {
                *(team + p1) = 1;
                *(team + p2) = 2;
            } else {
                *(team + p1) = t2 == 1 ? 2 : 1;
            }
        }
        if (t1 != -1) {
            if (t2 == -1) {
                *(team + p2) = t1 == 1 ? 2 : 1;
            } else {
                if (t1 == t2) {
                    impossible = 1;
                    continue;
                } 
            }
        }
    }
    if (impossible) {
        printf("IMPOSSIBLE");
    } else {
        for (int i = 0; i < m; ++i) {
            printf("%d ", *(team + i));
        }
    }
}

Test 1

Verdict: WRONG ANSWER

Test 2

Verdict: WRONG ANSWER

Test 3

Verdict: ACCEPTED

Test 4

Verdict: WRONG ANSWER

Test 5

Verdict: ACCEPTED

Test 6

Verdict: WRONG ANSWER

Test 7

Verdict: WRONG ANSWER

Test 8

Verdict: WRONG ANSWER

Test 9

Verdict: WRONG ANSWER

Test 10

Verdict: ACCEPTED

Test 11

Verdict: ACCEPTED

Test 12

Verdict: ACCEPTED