nr3.cpp: In function `int main()': nr3.cpp:12: warning: comparison between signed and unsigned integer expressions nr3.cpp:14: warning: comparison between signed and unsigned integer expressions nr3.cpp:27: warning: comparison between signed and unsigned integer expressions nr3.cpp:41: warning: comparison between signed and unsigned integer expressions /tmp/ccMapwWz.o(.text+0x47): In function `main': : the `gets' function is dangerous and should not be used.