Compilare: main.cpp: In function 'void solve(int, std::vector<std::pair<int, int> >&, bool)': main.cpp:51:17: warning: unused variable 'r' [-Wunused-variable] int r = sons[i][1]; ^ main.cpp: In function 'int i32()': main.cpp:22:32: warning: ignoring return value of 'size_t fread(void*, size_t, size_t, FILE*)', declared with attribute warn_unused_result [-Wunused-result] fread(buff,1,LEN,f); ^ main.cpp:30:32: warning: ignoring return value of 'size_t fread(void*, size_t, size_t, FILE*)', declared with attribute warn_unused_result [-Wunused-result] fread(buff,1,LEN,f); ^