Compilare: user.cpp: In function ‘int prim(int, int)’: user.cpp:80:40: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<cost[nod.v].size();i++) ^ user.cpp: In function ‘int main()’: user.cpp:122:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(j=0;j<apm[i].size();j++) ^ user.cpp:100:21: warning: unused variable ‘x0’ [-Wunused-variable] int m,n,i,j,x,y,x0; ^