Compilare: user.cpp: In function ‘int main()’: user.cpp:29:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<strlen(s);i++) ^ user.cpp:61:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<=strlen(s);i++) ^ user.cpp:21:16: warning: unused variable ‘j’ [-Wunused-variable] int k,i,ct,j,suma,y,w ; ^ user.cpp:21:25: warning: unused variable ‘w’ [-Wunused-variable] int k,i,ct,j,suma,y,w ; ^ /tmp/ccIPv4Xy.o: In function `main': user.cpp:(.text.startup+0x4e): warning: the `gets' function is dangerous and should not be used.