Compilare: user.c: In function ‘main’: user.c:147:5: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("heapuri.in", "r", stdin); ^ user.c:148:5: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("heapuri.out", "w", stdout); ^ user.c:174:5: warning: ignoring return value of ‘write’, declared with attribute warn_unused_result [-Wunused-result] write(1, obuf, obpos); ^ user.c: In function ‘write_int’: user.c:134:9: warning: ignoring return value of ‘write’, declared with attribute warn_unused_result [-Wunused-result] write(1, obuf, CHUNK); ^