Compilare: main.cpp: In function 'bool cmp(Pos, Pos)': main.cpp:40:25: warning: suggest parentheses around '&&' within '||' [-Wparentheses] if(a.x>b.x || a.x==b.x && a.y>b.y)return 0; ~~~~~~~~~^~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:87:10: warning: operation on 'i' may be undefined [-Wsequence-point] g<<vPos[--i].x<<' '<<vPos[i].y<<'\n'; ^~~ main.cpp:50:21: warning: unused variable 'b' [-Wunused-variable] int i,j,k,kk,n,m,a,b,x,y,dM[]={-1,0,1,0}; ^ main.cpp:50:23: warning: unused variable 'x' [-Wunused-variable] int i,j,k,kk,n,m,a,b,x,y,dM[]={-1,0,1,0}; ^ main.cpp:50:25: warning: unused variable 'y' [-Wunused-variable] int i,j,k,kk,n,m,a,b,x,y,dM[]={-1,0,1,0}; ^ main.cpp:51:10: warning: unused variable 'C' [-Wunused-variable] char ch,C[10002]; ^