Compilare: user.cpp: In function ‘int main()’: user.cpp:32:13: warning: variable ‘s’ set but not used [-Wunused-but-set-variable] int s; ^ user.cpp:12:33: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fin, "%d %d", &n, &M); ^ user.cpp:15:33: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fin, "%d", &v[i]); ^ user.cpp:28:37: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fin, "%d %d", &a, &b); ^