Compilare: main.cpp: In function 'void solve_test()': main.cpp:18:20: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &n); ^ main.cpp: In function 'int main()': main.cpp:33:38: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen ("input", "r", stdin); ^ main.cpp:34:40: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen ("output", "w", stdout); ^ main.cpp:36:24: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] files(FILENAME); ^ main.cpp:36:24: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] main.cpp:40:20: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &t); ^ main.cpp: In function 'void solve_test()': main.cpp:24:14: warning: 'j' may be used uninitialized in this function [-Wmaybe-uninitialized] ans -= j * j; ~~^~~