【HDOJ】4322 Candy

状态DP显然可以解，发现T了，不知道优化后能不能过。
然后发现费用流可以解。trick是对need拆解成need/K, need%K两种情况讨论。

 /* 4312 */

 #include <iostream>

 #include <sstream>

 #include <string>

 #include <map>

 #include <queue>

 #include <set>

 #include <stack>

 #include <vector>

 #include <deque>

 #include <algorithm>

 #include <cstdio>

 #include <cmath>

 #include <ctime>

 #include <cstring>

 #include <climits>

 #include <cctype>

 #include <cassert>

 #include <functional>

 #include <iterator>

 #include <iomanip>

 using namespace std;

 //#pragma comment(linker,"/STACK:102400000,1024000")

 #define sti                set<int>

 #define stpii            set<pair<int, int> >

 #define mpii            map<int,int>

 #define vi                vector<int>

 #define pii                pair<int,int>

 #define vpii            vector<pair<int,int> >

 #define rep(i, a, n)     for (int i=a;i<n;++i)

 #define per(i, a, n)     for (int i=n-1;i>=a;--i)

 #define clr                clear

 #define pb                 push_back

 #define mp                 make_pair

 #define fir                first

 #define sec                second

 #define all(x)             (x).begin(),(x).end()

 #define SZ(x)             ((int)(x).size())

 #define lson            l, mid, rt<<1

 #define rson            mid+1, r, rt<<1|1

 typedef struct {

     int v, w, f, nxt;

 } edge_t;

 const int INF = 0x3f3f3f3f;

 const int maxv = ;

 const int maxe = 1e5+;

 int need[maxv];

 int a[][];

 int head[maxv], l;

 edge_t E[maxe];

 int dis[maxv];

 int pre[maxv], ID[maxv];

 bool visit[maxv];

 int cost, flow;

 int n, m, K;

 const int ed = maxv - ;

 const int st = maxv - ;

 void init() {

     l = ;

     memset(head, -, sizeof(head));

 }

 void addEdge(int u, int v, int w, int c) {

     E[l].v = v;

     E[l].w = w;

     E[l].f = c;

     E[l].nxt = head[u];

     head[u] = l++;

     E[l].v = u;

     E[l].w = -w;

     E[l].f = ;

     E[l].nxt = head[v];

     head[v] = l++;

 }

 bool bfs() {

     queue<int> Q;

     int u, v, k;

     memset(dis, INF, sizeof(dis));

     memset(visit, false, sizeof(visit));

     Q.push(st);

     visit[st] = true;

     dis[st] = ;

     while (!Q.empty()) {

         u = Q.front();

         Q.pop();

         visit[u] = false;

         for (k=head[u]; k!=-; k=E[k].nxt) {

             v = E[k].v;

             if (E[k].f && dis[v]>dis[u]+E[k].w) {

                 dis[v] = dis[u] + E[k].w;

                 pre[v] = u;

                 ID[v] = k;

                 if (!visit[v]) {

                     visit[v] = true;

                     Q.push(v);

                 }

             }

         }

     }

     return dis[ed]==INF;

 }

 void MCMF() {

     int u, v, k;

     int tmp;

     flow = , cost = ;

     while () {

         if (bfs())

             break;

         tmp = INF;

         for (v=ed, u=pre[v]; v!=st; v=u, u=pre[v]) {

             k = ID[v];

             tmp = min(tmp, E[k].f);

         }

         for (v=ed, u=pre[v]; v!=st; v=u, u=pre[v]) {

             k = ID[v];

             E[k].f -= tmp;

             E[k^].f += tmp;

         }

         flow += tmp;

         cost += tmp * dis[ed];

     }

 }

 void solve() {

     int tot = , tmp;

     init();

     rep(i, , m)

         addEdge(st, i+n, , );

     rep(i, , n) {

         tot += need[i];

         rep(j, , m) {

             if (a[i][j])

                 addEdge(j+n, i, , );

         }

         tmp = need[i] / K;

         if (tmp) {

             addEdge(i, ed, -K, tmp);

         }

         tmp = need[i] % K;

         if (tmp > ) {

             addEdge(i, ed, -tmp, );

         }

     }

     MCMF();

     cost = -cost;

     if (cost+m-flow < tot)

         puts("NO");

     else

         puts("YES");

 }

 int main() {

     ios::sync_with_stdio(false);

     #ifndef ONLINE_JUDGE

         freopen("data.in", "r", stdin);

         freopen("data.out", "w", stdout);

     #endif

     int t;

     scanf("%d", &t);

     rep(tt, , t+) {

         scanf("%d %d %d", &m, &n, &K);

         rep(i, , n)

             scanf("%d", &need[i]);

         rep(i, , n)

             rep(j, , m)

                 scanf("%d", &a[i][j]);

         printf("Case #%d: ", tt);

         solve();

     }

     #ifndef ONLINE_JUDGE

         printf("time = %d.\n", (int)clock());

     #endif

     return ;

 }

数据发生器。

 from copy import deepcopy

 from random import randint, shuffle

 import shutil

 import string

 def GenDataIn():

     with open("data.in", "w") as fout:

         t = 50

         bound = 10**18

         fout.write("%d\n" % (t))

         for tt in xrange(t):

             m = randint(1, 13)

             n = randint(1, 13)

             k = randint(2, 10)

             fout.write("%d %d %d\n" % (m, n, k))

             L = []

             for i in xrange(n):

                 x = randint(1, 20)

                 L.append(x)

             fout.write(" ".join(map(str, L)) + "\n")

             for i in xrange(n):

                 L = []

                 for j in xrange(m):

                     x = randint(0, 1)

                     L.append(x)

                 fout.write(" ".join(map(str, L)) + "\n")

 def MovDataIn():

     desFileName = "F:\eclipse_prj\workspace\hdoj\data.in"

     shutil.copyfile("data.in", desFileName)

 if __name__ == "__main__":

     GenDataIn()

     MovDataIn()