Compilare: user.cpp: In function ‘int main()’: user.cpp:59:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<strlen(c);i++) ^ user.cpp:68:25: warning: array subscript has type ‘char’ [-Wchar-subscripts] v[peek()]=i; ^ user.cpp:57:13: warning: unused variable ‘k’ [-Wunused-variable] int m,i,k,v[100000],x; ^