Compilare: user.cpp: In function ‘int main()’: user.cpp:55:19: warning: unused variable ‘p2’ [-Wunused-variable] int n,m,i,x,y,p2,ct,a,b; ^~ user.cpp:56:32: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("lca.in","r",stdin); ^ user.cpp:57:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("lca.out","w",stdout); ^ user.cpp: In function ‘char getChar()’: user.cpp:17:28: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread(BUF,LIM,1,stdin); ^