foo.cpp: In function 'void input_data()':
foo.cpp:17:39: error: expression cannot be used as a function
 reach[i][j]=((x1[i]-x2[j])(x1[i]-x2[j])+(y1[i]-y2[j])(y1[i]-y2[j]))<=(k*k);//reach[i][j]??i??????j??????
                                       ^
foo.cpp:17:66: error: expression cannot be used as a function
 reach[i][j]=((x1[i]-x2[j])(x1[i]-x2[j])+(y1[i]-y2[j])(y1[i]-y2[j]))<=(k*k);//reach[i][j]??i??????j??????
                                                                  ^
foo.cpp: In function 'void search_ans(int, int)':
foo.cpp:78:25: error: name lookup of 'i' changed for ISO 'for' scoping [-fpermissive]
 memcpy(g[used],can[now][i],sizeof(can[now][i]));
                         ^
foo.cpp:78:25: note: (if you use '-fpermissive' G++ will accept your code)
foo.cpp:76:25: warning: unused variable 'k' [-Wunused-variable]
 while (head<tail) { int k=dl[++head];//???????? if (maxl<MAXT[now][k])//???????now?????????????? maxl=MAXT[now][k]; for (int i=1;i<used;i++)//??????????????????????????????????????????? if (g[i][k] && !vis[a[i]]) { vis[a[i]]=true; dl[++tail]=a[i]; } } if (maxl==now-1) return;//??????????????? used++; memcpy(g[used],can[now][maxl],sizeof(can[now][maxl]));//?????????????????????????????????? memcpy(tempa,a,sizeof(a));//???? memcpy(tempb,b,sizeof(b)); memset(vis,false,sizeof(vis));//???????? xiongyali(used);//?used?????? for (int i=maxl;i>=now;i--)//???????????perfect??????
                         ^
foo.cpp:85:1: error: a function-definition is not allowed here before '{' token
 {
 ^
foo.cpp:89:1: error: a function-definition is not allowed here before '{' token
 {
 ^
foo.cpp:67:23: warning: unused variable 'maxl' [-Wunused-variable]
 int tempa[l],tempb[l],maxl=now-1;//???????????
                       ^
foo.cpp:95:1: error: expected '}' at end of input
 }
 ^