CCF模拟题 最优配餐

 1 #include <bits/stdc++.h>
 2 #define pii pair<int,int>
 3 #define LL long long
 4 using namespace std;
 5 const int maxn = 1010;
 6 const int dir[4][2] = {-1,0,0,-1,1,0,0,1};
 7 int n,m,k,d,e[maxn][maxn] = {0};
 8 struct node {
 9     int x,y,step;
10     node(int a = 0,int b = 0,int c = 0) {
11         x = a;
12         y = b;
13         step = c;
14     }
15 };
16 queue<node>q;
17 bool isIn(int x,int y) {
18     return x > 0 && x <= n && y > 0 && y <= n;
19 }
20 LL bfs() {
21     LL ans = 0;
22     int cnt = 0;
23     while(!q.empty()) {
24         node now = q.front();
25         q.pop();
26         for(int i = 0; i < 4; ++i) {
27             int nx = now.x+ dir[i][0];
28             int ny = now.y + dir[i][1];
29             if(isIn(nx,ny)&&!(e[nx][ny]&1)) {
30                 e[nx][ny] |= 1;
31                 q.push(node(nx,ny,now.step+1));
32                 if(e[nx][ny]&2) {
33                     ans += (now.step+1)*(e[nx][ny]>>2);
34                     if(++cnt == k) return ans;
35                 }
36             }
37         }
38     }
39     return ans;
40 }
41 int main() {
42     int x,y,z;
43     while(~scanf("%d %d %d %d",&n,&m,&k,&d)) {
44         for(int i = 0; i < m; ++i) {
45             scanf("%d %d",&y,&x);
46             q.push(node(x,y,0));
47             e[x][y] |= 1;
48         }
49         for(int i = 0; i < k; ++i) {
50             scanf("%d %d %d",&y,&x,&z);
51             e[x][y] = (e[x][y]|2) + (z<<2);
52         }
53         for(int i = 0; i < d; ++i) {
54             scanf("%d %d",&y,&x);
55             e[x][y] |= 1;
56         }
57         printf("%I64d\n",bfs());
58     }
59     return 0;
60 }