Compilare: user.cpp: In function ‘void dfs(int)’: user.cpp:20:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (j=0;j<gf[x].size()&&ok;j++) ^ user.cpp: In function ‘void taie(int, int, int)’: user.cpp:46:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (val[i]==xyz[1]) ^ user.cpp:50:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (val[i]==xyz[2]) ^ user.cpp:62:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (val[i]==xyz[0]) ^ user.cpp:66:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (val[i]==xyz[2]) ^ user.cpp:77:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (val[i]==xyz[0]) ^ user.cpp:81:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (val[i]==xyz[1]) ^ user.cpp: In function ‘int main()’: user.cpp:109:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (val[j]==xyz[k]) ^ user.cpp:119:26: warning: suggest parentheses around assignment used as truth value [-Wparentheses] val[i]=viz[i]=t[i]=st[i]=0; ^