metrou.cpp: In function `void newChain(int)': metrou.cpp:56: warning: comparison between signed and unsigned integer expressions metrou.cpp:73: warning: comparison between signed and unsigned integer expressions metrou.cpp: In function `int solveChain()': metrou.cpp:111: warning: comparison between signed and unsigned integer expressions metrou.cpp:102: warning: `int x' might be used uninitialized in this function metrou.cpp: In function `int solve()': metrou.cpp:140: warning: comparison between signed and unsigned integer expressions metrou.cpp:155: warning: comparison between signed and unsigned integer expressions