ec.cpp: In function `bool do1()': ec.cpp:39: warning: comparison between signed and unsigned integer expressions ec.cpp: In function `bool do2()': ec.cpp:63: warning: comparison between signed and unsigned integer expressions ec.cpp:56: warning: `float x1' might be used uninitialized in this function ec.cpp:56: warning: `float x2' might be used uninitialized in this function ec.cpp: In function `int main()': ec.cpp:120: warning: comparison between signed and unsigned integer expressions