Compilare: user.cpp: In function ‘int rank(int (*)[100], int, int)’: user.cpp:22:19: warning: unused variable ‘k’ [-Wunused-variable] int i, j, r, c, k; ^ user.cpp: In function ‘int main()’: user.cpp:208:38: warning: format ‘%lf’ expects argument of type ‘double’, but argument 3 has type ‘int’ [-Wformat=] fprintf(stdout, "%.8lf ", 0); ^ user.cpp:125:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("gauss.out", "w", stdout); ^ user.cpp:127:29: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f, "%d %d", &M, &N); ^ user.cpp:130:28: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f, "%d", &val); ^