Compilare: user.cpp: In function 'int main()': user.cpp:41: warning: format '%s' expects type 'char*', but argument 3 has type 'char (*)[10000001]' user.cpp:42: warning: format '%s' expects type 'char*', but argument 3 has type 'char (*)[21]' user.cpp:52: warning: format '%s' expects type 'char*', but argument 3 has type 'char (*)[21]' user.cpp:87: warning: NULL used in arithmetic user.cpp: In function 'int sortf(const void*, const void*)': user.cpp:28: warning: control reaches end of non-void function