POJ 2516 Minimum Cost

  1 #include <iostream>
  2 #include <cstdio>
  3 #include <cstring>
  4 #include <cmath>
  5 #include <algorithm>
  6 #include <climits>
  7 #include <vector>
  8 #include <queue>
  9 #include <cstdlib>
 10 #include <string>
 11 #include <set>
 12 #include <stack>
 13 #define LL long long
 14 #define pii pair<int,int>
 15 #define INF 0x3f3f3f3f
 16 using namespace std;
 17 const int maxn = 200;
 18 struct arc {
 19     int v,w,f,next;
 20     arc(int x = 0,int y = 0,int z = 0,int nxt = 0) {
 21         v = x;
 22         w = y;
 23         f = z;
 24         next = nxt;
 25     }
 26 };
 27 arc e[10000];
 28 int head[maxn],d[maxn],p[maxn],tot,n,m,k,S,T;
 29 bool in[maxn];
 30 int need[maxn][maxn],supp[maxn][maxn];
 31 void add(int u,int v,int w,int f){
 32     e[tot] = arc(v,w,f,head[u]);
 33     head[u] = tot++;
 34     e[tot] = arc(u,-w,0,head[v]);
 35     head[v] = tot++;
 36 }
 37 bool spfa() {
 38     for(int i = S; i <= T; i++) {
 39         in[i] = false;
 40         d[i] = INF;
 41         p[i] = -1;
 42     }
 43     queue<int>q;
 44     d[S] = 0;
 45     in[S]  =true;
 46     q.push(S);
 47     while(!q.empty()) {
 48         int u = q.front();
 49         q.pop();
 50         in[u] = false;
 51         for(int i = head[u]; ~i; i = e[i].next) {
 52             if(e[i].f > 0 && d[e[i].v] > d[u] + e[i].w) {
 53                 d[e[i].v] = d[u] + e[i].w;
 54                 p[e[i].v] = i;
 55                 if(!in[e[i].v]) {
 56                     q.push(e[i].v);
 57                     in[e[i].v] = true;
 58                 }
 59             }
 60         }
 61     }
 62     return p[T] > -1;
 63 }
 64 int solve() {
 65     int tmp = 0,theMin;
 66     while(spfa()) {
 67         theMin = INF;
 68         for(int i = p[T]; ~i; i = p[e[i^1].v])
 69             theMin = min(theMin,e[i].f);
 70         for(int i = p[T]; ~i; i = p[e[i^1].v]) {
 71             e[i].f -= theMin;
 72             e[i^1].f += theMin;
 73             tmp += e[i].w*theMin;
 74         }
 75     }
 76     return tmp;
 77 }
 78 int main() {
 79     bool flag;
 80     int tmp,ans;
 81     while(scanf("%d %d %d",&n,&m,&k),n||m||k) {
 82         for(int i = 1; i <= n; i++)
 83             for(int j = 1; j <= k; j++)
 84                 scanf("%d",need[i]+j);
 85         for(int i = 1; i <= m; i++)
 86             for(int j = 1; j <= k; j++)
 87                 scanf("%d",supp[i]+j);
 88         flag = true;
 89         for(int i = 1; i <= k; i++){
 90             int sum = 0;
 91             for(int j = 1; j <= m; j++)
 92                 sum += supp[j][i];
 93             for(int j = 1; j <= n; j++)
 94                 sum -= need[j][i];
 95             if(sum < 0){flag = false;break;}
 96         }
 97         S = ans = 0;
 98         T = n+m+1;
 99         for(int i = 1; i <= k; i++){
100             memset(head,-1,sizeof(head));
101             tot = 0;
102             for(int j = 1; j <= m; j++)
103                 add(S,j,0,supp[j][i]);
104             for(int j = 1; j <= n; j++){
105                 add(m+j,T,0,need[j][i]);
106                 for(int t = 1; t <= m; t++){
107                     scanf("%d",&tmp);
108                     add(t,m+j,tmp,INF);
109                 }
110             }
111             if(flag) ans += solve();
112         }
113         printf("%d\n",flag?ans:-1);
114     }
115     return 0;
116 }