Compilare: user.cpp: In function ‘kdnod* build(std::vector<punct>&, int)’: user.cpp:104:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < v.size(); i++) ^ user.cpp:105:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (i == v.size()/2) continue; ^ user.cpp:114:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < v.size(); i++) ^ user.cpp:115:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (i == v.size()/2) continue; ^ user.cpp: In function ‘char getChar()’: user.cpp:24:34: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread(buf, 1, DIM, stdin); ^ user.cpp: In function ‘int main()’: user.cpp:177:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("zoo.in", "r", stdin); ^ user.cpp:178:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("zoo.out", "w", stdout); ^ user.cpp:180:27: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread(buf, 1, DIM, stdin); ^