HDU-3338 Kakuro Extension (maximum flow)

The main idea of the topic: to see a basic

Problem solving idea: the difficulty is the composition.
Sets a super source point and all the rows and connections, and the capacity for that row and-the line and is added by several numbers to get
Sets a super sink, and all columns are concatenated, and the capacity is the sum of the columns-and the columns are added by a few numbers
Then there's the white space and the "Row and" and "column and" relationships.
Whitespace is connected to the line and, the weight value is 8
The blank is connected to the column's columns, and the weight value is 8.
Why is 8, not 9, because the traffic may also be 0, but 0 is not filled, so the capacity is set to 8, the last value of the time to add 1 can

#include <cstdio>#include <cstring>#include <algorithm>#include <vector>#include <queue>using namespace STD;#define N 100010#define INF 0x3f3f3f3fstructEdge {intFrom, to, cap, flow; Edge () {} Edge (intFromintTo,intCapintFlow): From, to, Cap (CAP), flow (flow) {}};structISAP {intP[n], Num[n], cur[n], d[n];intT, S, N, M;BOOLVis[n]; vector<int>G[n]; vector<Edge>EdgesvoidInitintN) { This->n = n; for(inti =0; I <= N;            i++) {g[i].clear ();        D[i] = INF;    } edges.clear (); }voidAddedge (intFromintTo,intCAP) {Edges.push_back (Edge (from, to, Cap,0)); Edges.push_back (Edge (to, from,0,0));        m = Edges.size (); G[from].push_back (M-2); G[to].push_back (M-1); }BOOLBFS () {memset(Vis,0,sizeof(VIS)); Queue<int>Q; D[T] =0; VIS[T] =1; Q.push (t); while(! Q.empty ()) {intU = Q.front (); Q.pop (); for(inti =0; I < g[u].size (); i++) {Edge &e = edges[g[u][i] ^1];if(!vis[e.from] && e.cap > E.flow) {Vis[e.from] =true; D[e.from] = D[u] +1;                Q.push (E.from); }            }        }returnVis[s]; }intAugment () {intU = T, flow = INF; while(U! = s)            {Edge &e = edges[p[u]];            flow = min (flow, e.cap-e.flow);        u = edges[p[u]].from; } u = t; while(U! = s)            {Edges[p[u]].flow + = flow; Edges[p[u] ^1].flow-= flow;        u = edges[p[u]].from; }returnFlow }intMaxflow (intSintT) { This->s = s; This->t = t;intFlow =0; BFS ();if(D[s] > N)return 0;memset(Num,0,sizeof(num));memset(cur,0,sizeof(cur)); for(inti =0; I < n; i++)if(D[i] < INF) num[d[i]]++;intU = s; while(D[s] <= N) {if(U = = t)                {Flow + = Augment ();            U = s; }BOOLOK =false; for(inti = Cur[u]; I < g[u].size (); i++) {Edge &e = edges[g[u][i]];if(E.cap > E.flow && d[u] = = D[e.to] +1) {OK =true;                     P[e.to] = G[u][i];                    Cur[u] = i; u = e.to; Break; }            }if(!ok) {intMin = n; for(inti =0; I < g[u].size (); i++) {Edge &e = edges[g[u][i]];if(E.cap > E.flow)                min = min (min, d[e.to]); }if(--num[d[u]] = =0) Break; Num[d[u] = Min +1]++; Cur[u] =0;if(U! = s) u = edges[p[u]].from; }        }returnFlow }};isap ISAP;#define MstructNode {intRow, Col, Val; Node () {} node (intRowintColintval): Row (Row), col (Col), Val (val) {}}row[n], col[n];intN, M;intEMPTY[M][M];Char Map[M];voidSolve () {intCnt_row =0, Cnt_col =0, Cnt_empty =0;memset(Empty,0,sizeof(empty)); for(inti =1; I <= N; i++) for(intj =1; J <= M; J + +) {scanf('%s ',Map);if(strcmp(Map,".......") ==0) Empty[i][j] = ++cnt_empty;Else if(Map[3] ==' \ \ ') {intTif(Map[0] !=' X ') {T = (Map[0] -' 0 ') * -+ (Map[1] -' 0 ') *Ten+ (Map[2] -' 0 ');                Col[++cnt_col] = Node (i, J, T); }if(Map[4] !=' X ') {T = (Map[4] -' 0 ') * -+ (Map[5] -' 0 ') *Ten+ (Map[6] -' 0 ');               Row[++cnt_row] = Node (i, J, T); }                }        }ints =0, T = cnt_empty + cnt_row + cnt_col +1; Isap.init (t); for(inti =1; I <= Cnt_row; i++) {intx = Row[i].row;intCNT =0; for(inty = Row[i].col +1; Y <= m; y++) {if(Empty[x][y])                {cnt++; Isap. Addedge (i, Cnt_row + empty[x][y],8); }Else                 Break; } ISAP.    Addedge (S, I, row[i].val-cnt); } for(inti =1; I <= Cnt_col; i++) {inty = Col[i].col;intCNT =0; for(intx = Col[i].row +1; x <= N; X + +) {if(Empty[x][y])                {cnt++; Isap. Addedge (Cnt_row + empty[x][y], Cnt_row + cnt_empty + I,8); }Else                  Break; } ISAP.    Addedge (Cnt_row + cnt_empty + I, T, col[i].val-cnt); } ISAP. Maxflow (S, t); for(inti =1; I <= N; i++) { for(intj =1; J <= M; J + +) {if(Empty[i][j]) {intAns =0; for(intK =0; K < Isap. G[EMPTY[I][J] + cnt_row].size (); k++) {Edge &e = Isap.edges[isap. G[EMPTY[I][J] + cnt_row][k]];if(E.to > Cnt_row + cnt_empty) {ans + = E.flow; Break; }                }printf("%d", ans +1); }Else                printf("_ "); }printf("\ n"); }}intMain () { while(scanf("%d%d", &n, &m)! = EOF) {solve (); }return 0;}

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HDU-3338 Kakuro Extension (maximum flow)