Compilare: main.cpp: In function 'int main()': main.cpp:43:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i = 0 ; i < v.size() ; i ++) ~~^~~~~~~~~~ main.cpp:44:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(j = i + 1 ; j < v.size() ; j ++) ~~^~~~~~~~~~ main.cpp:53:39: warning: format '%d' expects argument of type 'int', but argument 2 has type 'std::vector<armonica>::size_type {aka long unsigned int}' [-Wformat=] printf("%d\n" , 2 * ans.size() - 1); ^ main.cpp:54:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i = 0 ; i < ans.size() ; i ++) ~~^~~~~~~~~~~~ main.cpp:27:36: warning: unused variable 'aux' [-Wunused-variable] long long b , bb , d , i , j , aux; ^~~ main.cpp:25:41: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("armonica.in" , "r" , stdin); ^ main.cpp:26:43: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("armonica.out" , "w" , stdout); ^ main.cpp:28:23: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%lld" , &b); ^