tgv.cpp: In function `void DFS(int, int)': tgv.cpp:20: warning: comparison between signed and unsigned integer expressions tgv.cpp:24: warning: comparison between signed and unsigned integer expressions tgv.cpp:27: warning: comparison between signed and unsigned integer expressions tgv.cpp:35: warning: comparison between signed and unsigned integer expressions tgv.cpp:18: warning: unused variable `int J' tgv.cpp:18: warning: `int I' might be used uninitialized in this function