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老wa 那位兄弟帮忙看看或者给点数据测测
二分法 + 2sat
#include <iostream>
#include <iomanip>
#include <cmath>
#include <string>
#include <vector>
using namespace std;
#define min(a, b) ((a) < (b) ? (a):(b))
#define max(a, b) ((a) > (b) ? (a):(b))
#define MAXIN 500
int N, A, B;
int sx1, sy1, sx2, sy2;
int xy[MAXIN][2];
int Dij;
bool G[MAXIN*2][MAXIN*2];
bool TG[MAXIN*2][MAXIN*2];
bool Gr[MAXIN*2][MAXIN*2];
bool TGr[MAXIN*2][MAXIN*2];
bool visited[MAXIN*2];
int finished[MAXIN*2];
int cid[MAXIN*2];
unsigned long ans;
void fDFS(int i)
{
static index = 0;
visited[i] = true;
int k;
for(k = 0; k < 2*N; k ++)
{
if(G[i][k] && !visited[k])
fDFS(k);
}
finished[index++] = i;
}
void bDFS(int i, int id)
{
visited[i] = false;
cid[i] = id;
int k;
for(k = 0; k < 2*N; k ++)
{
if(Gr[i][k] && visited[k])
bDFS(k, id);
}
}
bool check()
{
int i;
for(i = 0; i < 2*N; i ++)
if(!visited[i])
fDFS(i);
int id = 0;
for(i = 2*N - 1; i >= 0; i --)
if(visited[finished[i]])
bDFS(finished[i], id ++);
for(i = 0; i < N; i ++)
{
if(cid[2*i] == cid[2*i + 1])
return false;
}
return true;
}
bool checkdist(int mid)
{
int i, j;
for(i = 0; i < N; i ++)
for(j = i + 1; j < N; j ++)
{
if(xy[i][0] + xy[j][0] > mid)
{
G[2*i][2*j + 1] = 1;
Gr[2*j + 1][2*i] = 1;
G[2*j][2*i + 1] = 1;
Gr[2*i + 1][2*j] = 1;
}
if(xy[i][1] + xy[j][1] > mid)
{
G[2*i + 1][2*j] = 1;
Gr[2*j][2*i + 1] = 1;
G[2*j + 1][2*i] = 1;
Gr[2*i][2*j + 1] = 1;
}
if(xy[i][0] + Dij + xy[j][1] > mid)
{
G[2*i][2*j] = 1;
Gr[2*j][2*i] = 1;
G[2*j + 1][2*i + 1] = 1;
Gr[2*i + 1][2*j + 1] = 1;
}
if(xy[i][1] + Dij + xy[j][0] > mid)
{
G[2*i + 1][2*j + 1] = 1;
Gr[2*j + 1][2*i + 1] = 1;
G[2*j][2*i] = 1;
Gr[2*i][2*j] = 1;
}
}
return check();
}
void main()
{
memset(G, 0, 1000*1000);
memset(TG, 0, 1000*1000);
memset(Gr, 0, 1000*1000);
memset(TGr, 0, 1000*1000);
memset(visited, 0, 1000);
scanf("%d %d %d", &N, &A, &B);
scanf("%d %d %d %d", &sx1, &sy1, &sx2, &sy2);
int i, j;
for(i = 0; i < N; i ++)
{
scanf("%d %d", &xy[i][0], &xy[i][1]);
}
int t1, t2;
for(i = 0; i < A; i ++)
{
scanf("%d %d", &t1, &t2);
t1 --;
t2 --;
G[t1*2 + 1][t2*2] = G[t2*2][t1*2 + 1] = 1;
G[t2*2 + 1][t1*2] = G[t1*2][t2*2 + 1] = 1;
Gr[t1*2 + 1][t2*2] = Gr[t2*2][t1*2 + 1] = 1;
Gr[t2*2 + 1][t1*2] = Gr[t1*2][t2*2 + 1] = 1;
}
for(i = 0; i < B; i ++)
{
scanf("%d %d", &t1, &t2);
t1 --;
t2 --;
G[t1*2 + 1][t2*2 + 1] = G[t2*2 + 1][t1*2 + 1] = 1;
G[t2*2][t1*2] = G[t1*2][t2*2] = 1;
Gr[t1*2 + 1][t2*2 + 1] = Gr[t2*2 + 1][t1*2 + 1] = 1;
Gr[t2*2][t1*2] = Gr[t1*2][t2*2] = 1;
}
if(!check())
printf("-1\n");
else
{
for(i = 0; i < 2*N; i ++)
for(j = 0; j < 2*N; j ++)
{
TG[i][j] = G[i][j];
TGr[i][j] = Gr[i][j];
}
Dij = abs(sx1 - sx2) + abs(sy1 - sy2);
int max1 = 0, max2 = 0;
for(i = 0; i < N; i ++)
{
t1 = abs(xy[i][0] - sx1) + abs(xy[i][1] - sy1);
t2 = abs(xy[i][0] - sx2) + abs(xy[i][1] - sy2);
xy[i][0] = t1;
xy[i][1] = t2;
max1 = max(xy[i][0], max1);
max2 = max(xy[i][1], max2);
}
int high = max(max1 + max2 + Dij, max1*2);
high = max(high, max2*2);
int low = 0;
int mid;
while(high > low)
{
mid = (high + low)/2;
if(checkdist(mid))
high = mid;
else
low = mid + 1;
for(i = 0; i < 2*N; i ++)
for(j = 0; j < 2*N; j ++)
{
G[i][j] = TG[i][j];
Gr[i][j] = TGr[i][j];
}
}
printf("%d\n", high);
}
}
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