[BJOI2006]狼抓兔子 暴力AC啦！

  1 #include <map>
  2 #include <set>
  3 #include <cmath>
  4 #include <ctime>
  5 #include <queue>
  6 #include <stack>
  7 #include <vector>
  8 #include <bitset>
  9 #include <cstdio>
 10 #include <cctype>
 11 #include <string>
 12 #include <cstring>
 13 #include <cassert>
 14 #include <climits>
 15 #include <cstdlib>
 16 #include <iostream>
 17 #include <algorithm>
 18 #include <functional>
 19 using namespace std ;
 20 
 21 #define rep(i, a, b) for (int (i) = (a); (i) <= (b); (i)++)
 22 #define Rep(i, a, b) for (int (i) = (a) - 1; (i) < (b); (i)++)
 23 #define REP(i, a, b) for (int (i) = (a); (i) >= (b); (i)--)
 24 #define clr(a) memset(a, 0, sizeof(a))
 25 #define Sort(a, len, cmp) sort(a + 1, a + len + 1, cmp)
 26 #define ass(a, sum) memset(a, sum, sizeof(a))
 27 
 28 #define ls ((rt) << 1)
 29 #define rs ((rt) << 1 | 1)
 30 #define lowbit(x) (x & -x)
 31 #define mp make_pair
 32 #define pb push_back
 33 #define fi first
 34 #define se second
 35 #define endl ‘\n‘
 36 #define ENDL cout << endl
 37 #define SZ(x) ((int)x.size())
 38 
 39 typedef long long ll ;
 40 typedef unsigned long long ull ;
 41 typedef vector <int> vi ;
 42 typedef pair <int, int> pii ;
 43 typedef pair <ll, ll> pll ;
 44 typedef map <int, int> mii ;
 45 typedef map <string, int> msi ;
 46 typedef map <ll, ll> mll ;
 47 
 48 const int N = 1010 ;
 49 const double eps = 1e-8 ;
 50 const int iinf = INT_MAX ;
 51 const ll linf = 2e18 ;
 52 const double dinf = 1e30 ;
 53 const int MOD = 1000000007 ;
 54 
 55 inline int read(){
 56     int X = 0, w = 0 ;
 57     char ch = 0 ;
 58     while (!isdigit(ch)) { w |= ch == ‘-‘ ; ch = getchar() ; }
 59     while (isdigit(ch)) X = (X << 3) + (X << 1) + (ch ^ 48), ch = getchar() ;
 60     return w ? - X : X ;
 61 }
 62 
 63 void write(int x){
 64      if (x < 0) putchar(‘-‘), x = - x ;
 65      if (x > 9) write(x / 10) ;
 66      putchar(x % 10 + ‘0‘) ;
 67 }
 68 
 69 void print(int x) {
 70     cout << x << endl ;
 71     exit(0) ;
 72 }
 73 
 74 void PRINT(string x) {
 75     cout << x << endl ;
 76     exit(0) ;
 77 }
 78 
 79 void douout(double x){
 80      printf("%lf\n", x + 0.0000000001) ;
 81 }
 82 
 83 int n, m, x, top = 1, s, t ;
 84 int head[N * N], dep[N * N] ;
 85 
 86 struct Edge {
 87     int to, nxt, w ;
 88 } e[N * N * 6] ;
 89 
 90 void add(int a, int b, int w) {
 91     e[++top] = (Edge) {b, head[a], w} ;
 92     head[a] = top ;
 93 }
 94 
 95 void insert(int a, int b, int w) {
 96     add(a, b, w) ;
 97     add(b, a, w) ;
 98 }
 99 
100 bool bfs() { //分层图
101     queue <int> q ;
102     q.push(s) ;
103     clr(dep) ;
104     dep[s] = 1 ;
105     while (!q.empty()) {
106         int now = q.front() ;
107         q.pop() ;
108         for (int i = head[now]; i; i = e[i].nxt) {
109             int to = e[i].to ;
110             if (e[i].w && !dep[to]) {
111                 dep[to] = dep[now] + 1 ;
112                 q.push(to) ;
113             }
114         }
115     }
116     if (!dep[t]) return 0 ;
117     else return 1 ;
118 }
119 
120 int dfs(int rt, int dis) {
121     if (rt == t) return dis ;
122     for (int i = head[rt]; i; i = e[i].nxt) {
123         int to = e[i].to ;
124         if (dep[to] == dep[rt] + 1 && e[i].w) {
125             int p = dfs(to, min(e[i].w, dis));
126             if (!p) {
127                 dep[to] = -1;
128                 continue;
129             }
130             e[i].w -= p ;
131             e[i ^ 1].w += p ;
132             return p ;
133         }
134     }
135     return 0 ;
136 }
137 
138 int dinic() {
139     int res = 0 ;
140     while (bfs()) {
141         while (int d = dfs(s, iinf)) res += d ;
142     }
143     return res ;
144 }
145 
146 int id(int x, int y) {
147     return (x - 1) * m + y ;
148 }
149 
150 signed main(){
151     scanf("%d%d", &n, &m) ;
152     s = 1, t = id(n, m) ;
153     for (int i = 1; i <= n; i++)
154     for (int j = 1; j < m; j++) {
155         scanf("%d", &x) ;
156         insert(id(i, j), id(i, j + 1), x) ;
157     }
158     for (int i = 1; i < n; i++)
159     for (int j = 1; j <= m; j++) {
160         scanf("%d", &x) ;
161         insert(id(i, j), id(i + 1, j), x) ;
162     }
163     for (int i = 1; i < n; i++)
164     for (int j = 1; j < m; j++) {
165         scanf("%d", &x) ;
166         insert(id(i, j), id(i + 1, j + 1), x) ;
167     }
168     printf("%d\n", dinic()) ;
169 }
170 
171 /*
172 写代码时请注意：
173     1.是否要开Long Long？数组边界处理好了么？
174     2.实数精度有没有处理？
175     3.特殊情况处理好了么？
176     4.做一些总比不做好。
177 思考提醒：
178     1.最大值和最小值问题可不可以用二分答案？
179     2.有没有贪心策略？否则能不能dp？
180 */