Compilare: main.cpp: In function 'int build()': main.cpp:27:1: warning: no return statement in function returning non-void [-Wreturn-type] } ^ main.cpp: In function 'int main()': main.cpp:36:38: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("coins.in" , "r" , stdin); ^ main.cpp:37:40: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("coins.out" , "w" , stdout); ^ main.cpp:39:21: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d" , &n); ^ main.cpp:48:30: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%1d" , &c); ^