litere.cpp: In function `int isPoz(char*, char)': litere.cpp:21: warning: comparison between signed and unsigned integer expressions litere.cpp: In function `int main()': litere.cpp:46: warning: comparison between signed and unsigned integer expressions litere.cpp:53: warning: comparison between signed and unsigned integer expressions litere.cpp:59: warning: assignment to non-pointer type `char' from NULL litere.cpp:59: warning: argument to non-pointer type `char' from NULL litere.cpp:62: warning: comparison between signed and unsigned integer expressions