Compilare: main.cpp: In function 'int main()': main.cpp:70:32: warning: format '%d' expects argument of type 'int', but argument 2 has type 'std::vector<int>::size_type {aka long unsigned int}' [-Wformat=] printf("%d",C[1].size()); ^ main.cpp:48:36: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("ninjago.in","r",stdin); ^ main.cpp:49:38: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("ninjago.out","w",stdout); ^