有源匯上下界最大流，行列建圖，下界為ai,j，上界為ai,j+1，跑的飛起。
不要忘記判斷上取整下取整相同的情況。

#include<iostream> #include<cstdio> #include<cstring> #define inf 1000000007 #define N 205 #define M 30005 using namespace std; int n,cnt=1,S,T,SS,TT,total,ans; int head[N],cur[N],dis[N],q[N],du[N]; int next[M],list[M],key[M]; double a[N>>1][N>>1]; int l[N>>1][N>>1]; inline void insert(int x,int y,int z) {next[++cnt]=head[x];head[x]=cnt;list[cnt]=y;key[cnt]=z; } inline bool BFS(int S,int T) {int t=0,w=1,x;memset(dis,-1,sizeof(dis));dis[S]=1; q[1]=S;while (t<w){x=q[++t];for (int i=head[x];i;i=next[i])if (key[i]&&dis[list[i]]==-1)dis[q[++w]=list[i]]=dis[x]+1;}return dis[T]!=-1; } int find(int x,int flow,int T) {if (x==T) return flow;int w,used=0;for (int i=cur[x];i;i=next[i])if (key[i]&&dis[list[i]]==dis[x]+1){w=find(list[i],min(flow-used,key[i]),T);key[i]-=w; key[i^1]+=w; used+=w;if (key[i]) cur[x]=i;if (used==flow) return flow;}if (!used) dis[x]=-1;return used; } inline int dinic(int S,int T) {int ans=0;while (BFS(S,T)){for (int i=0;i<=T;i++) cur[i]=head[i];ans+=find(S,inf,T);}return ans; } int main() {scanf("%d",&n); n--; S=0; T=n<<1|1; SS=T+1; TT=T+2;for (int i=1;i<=n+1;i++)for (int j=1;j<=n+1;j++)scanf("%lf",&a[i][j]),l[i][j]=(int)a[i][j];for (int i=1;i<=n;i++){du[i]+=l[i][n+1],du[S]-=l[i][n+1];if (a[i][n+1]!=l[i][n+1]) insert(S,i,1),insert(i,S,0);}for (int i=1;i<=n;i++){du[i+n]-=l[n+1][i],du[T]+=l[n+1][i];if (a[n+1][i]!=l[n+1][i]) insert(i+n,T,1),insert(T,i+n,0);}for (int i=1;i<=n;i++)for (int j=1;j<=n;j++){du[i]-=l[i][j],du[j+n]+=l[i][j];if (a[i][j]!=l[i][j]) insert(i,j+n,1),insert(j+n,i,0);}for (int i=0;i<=T;i++)if (du[i]>0) total+=du[i],insert(SS,i,du[i]),insert(i,SS,0);else if (du[i]<0) insert(i,TT,-du[i]),insert(TT,i,0);insert(T,S,inf); insert(S,T,0);ans=dinic(SS,TT);if (ans!=total) puts("No");else ans=dinic(S,T),printf("%d\n",3*ans);return 0; }

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