Compilare: user.cpp: In function ‘int main()’: user.cpp:44:9: warning: unused variable ‘l’ [-Wunused-variable] int l = 0; ^ user.cpp:45:9: warning: unused variable ‘col’ [-Wunused-variable] int col = 0; ^ user.cpp:28:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("balans.in", "r", stdin); ^ user.cpp:29:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("balans.out", "w", stdout); ^ user.cpp:31:38: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d%d", &n, &m, &r, &c); ^ user.cpp:36:34: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &M[i][j]); ^