Problem with main() and no output root file

Newbie
5

Fix your source code.

[...]$ `root-config --cxx --cflags` -Wall main.cc `root-config --libs`
/usr/bin/ld: /tmp/ccykh63G.o: in function `main':
main.cc:(.text+0x1f0): undefined reference to `particle_tree::particle_tree(char const*)'
/usr/bin/ld: main.cc:(.text+0x42f): undefined reference to `particle_tree::GetEntry(long long)'
/usr/bin/ld: main.cc:(.text+0x6db): undefined reference to `particle_tree::~particle_tree()'
/usr/bin/ld: main.cc:(.text+0x78a): undefined reference to `particle_tree::~particle_tree()'
collect2: error: ld returned 1 exit status