Compilare: main.cpp: In function 'int main()': main.cpp:14:18: warning: statement has no effect [-Wunused-value] for(k; k + 4 <= i ; k += 4){ ^ main.cpp:20:18: warning: statement has no effect [-Wunused-value] for(k; k <= i ; ++k) ^ main.cpp:7:35: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("tije.in", "r", stdin); ^ main.cpp:8:37: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("tije.out", "w", stdout); ^ main.cpp:10:20: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &n); ^