Compilare: user.cpp: In function ‘int main()’: user.cpp:20:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < m; ++i) ^ user.cpp:21:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int j = 0; j < m; ++j) ^ user.cpp:25:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0, val; i < n; ++i){ ^ user.cpp:27:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int j = 0; j < n; ++j){ ^ user.cpp:37:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < m; ++i){ ^ user.cpp:39:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int j = 0; j < m; ++j){ ^ user.cpp:40:13: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (j >= n) ^ user.cpp:46:13: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (i >= n) ^ user.cpp:49:13: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (j >= n) Hash[i][j] = Rhash2; ^ user.cpp:51:13: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (i >= n && Rhash2 == Rhash) ^ user.cpp:15:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("tetris2.in", "r", stdin); ^ user.cpp:16:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("tetris2.out", "w", stdout); ^ user.cpp:19:19: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d\n", &m); ^ user.cpp:22:26: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d ", &M[i][j]); ^ user.cpp:24:17: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &n); ^ user.cpp:28:21: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &val); ^