Eroare de compilare: user.cpp: In function ‘int main()’: user.cpp:25:24: error: invalid conversion from ‘char’ to ‘const char*’ [-fpermissive] nr=atoll(ch); ^ In file included from /usr/include/features.h:357:0, from /usr/include/i386-linux-gnu/c++/4.8/bits/os_defines.h:39, from /usr/include/i386-linux-gnu/c++/4.8/bits/c++config.h:420, from /usr/include/c++/4.8/iostream:38, from user.cpp:1: /usr/include/stdlib.h:298:1: error: initializing argument 1 of ‘long long int atoll(const char*)’ [-fpermissive] __NTH (atoll (__const char *__nptr)) ^ user.cpp:13:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("trompeta.in","r",stdin); ^ user.cpp:14:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("trompeta.out","w",stdout); ^