Compilare: user.cpp: In function ‘int main()’: user.cpp:20:22: warning: suggest parentheses around ‘-’ inside ‘<<’ [-Wparentheses] d[i][j]=1<<31-1; ^ user.cpp:26:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (j=0;j<v[x].size();j++) ^ user.cpp:35:27: warning: suggest parentheses around ‘-’ inside ‘<<’ [-Wparentheses] if (d[i][j]==1<<31-1 && d[j][i]==1<<31-1) ok=false; ^ user.cpp:35:47: warning: suggest parentheses around ‘-’ inside ‘<<’ [-Wparentheses] if (d[i][j]==1<<31-1 && d[j][i]==1<<31-1) ok=false; ^