Compilare: user.cpp: In function ‘void solve()’: user.cpp:72:9: warning: unused variable ‘i’ [-Wunused-variable] int i; ^ user.cpp: In function ‘void readFile()’: user.cpp:48:24: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f, "%d", &n); ^ user.cpp:53:44: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f, "%d%d", &v[i].a, &v[i].b); ^