Compilare: user.c: In function ‘bfs’: user.c:15:3: warning: implicit declaration of function ‘memset’ [-Wimplicit-function-declaration] memset(tr, 0, sizeof tr); ^ user.c:15:3: warning: incompatible implicit declaration of built-in function ‘memset’ [enabled by default] user.c:17:10: warning: unused variable ‘k’ [-Wunused-variable] int a, k, poz, st = 0, dr = 1; ^ user.c: In function ‘main’: user.c:41:9: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result] fscanf(in, "%d%d", &n, &m); ^ user.c:45:11: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result] fscanf(in, "%d%d%d", &x, &y, &z); ^