Compilare: user.cpp: In function ‘int compara(char*, char*)’: user.cpp:30:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(i<strlen(a)) ^ user.cpp: In function ‘int main()’: user.cpp:53:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<strlen(s);i++) ^ user.cpp:85:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<=strlen(s);i++) ^ user.cpp:45:30: warning: unused variable ‘w’ [-Wunused-variable] int k,i,ct,j,suma,y,ok,q,w,aux ; ^ /tmp/cc8hij6I.o: In function `main': user.cpp:(.text.startup+0x4e): warning: the `gets' function is dangerous and should not be used.