Compilare: main.cpp: In function 'int main()': main.cpp:34:27: warning: format '%d' expects argument of type 'int', but argument 2 has type 'std::stack<char>::size_type {aka long unsigned int}' [-Wformat=] printf("%d",q.size()/2); ^ main.cpp:7:32: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("par.in","r",stdin); ^ main.cpp:8:34: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("par.out","w",stdout); ^ main.cpp:11:21: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d\n",&n); ^ main.cpp:19:23: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%c",&c); ^