Compilare: main.cpp: In function 'int main()': main.cpp:63:49: warning: use of 'll' length modifier with 'f' type character has either no effect or undefined behavior [-Wformat=] printf("%.5llf" , abs(-0.5 * area(sequence))); ^ main.cpp:53:37: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("aria.in" , "r" , stdin); ^ main.cpp:54:39: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("aria.out" , "w" , stdout); ^