POJ1185 Artillery Positions

The main topic: In a n*m area, p is plain, h is mountainous. The plains can be put into artillery units, and the mountains cannot. Each artillery unit may be injured in a companion or in the same " -2,+2" range of friendlies. Under the premise of guaranteeing no injury, ask the area to be able to decorate the maximum number of artillery. N<=100,m<10

Analysis: processing by row. The state of each row can be processed with DFS and saved in the array.

F[i][j][k]=∑ (F[[i-1][k][p])

F[I][J][K] Indicates the maximum number of artillery that can be arranged when the state of line I is J and the previous row has a state of K.

J and K can not conflict, J and P also can not conflict, K and P can not conflict. f The initial value is 0.

1#include <iostream>2#include <cstdio>3#include <cstring>4#include <vector>5#include <cstring>6 using namespacestd;7 #defineMAXN 1058 intF[maxn][maxn][maxn],n,m,state[maxn][maxn],row,cnt,cnts[maxn][maxn],nums[maxn],num;9 CharARR[MAXN][MAXN];Ten voidDfsintJintStaintCNT) One { A   if(j>m) -   { -state[row][num++]=STA; thecnts[row][num-1]=CNT; -nums[row]=num; -       return; -   } +     if((sta&3)==0&&arr[row][j]=='P') -DFS (j+1, (sta<<1)+1, cnt+1); +DFS (j+1, (sta<<1), CNT); A } at intMain () - { -scanf"%d%d",&n,&m); -   for(intI=1; i<=n;i++) -{scanf ("%s", arr[i]+1); -row=i; innum=0; -Dfs1,0,0); to   } +Memset (F,0,sizeoff); -    for(intI=0; i<nums[1];i++) thef[1][i][0]=cnts[1][i]; *nums[0]=1; $   for(intI=2; i<=n;i++)Panax Notoginseng     for(intj=0; j<nums[i];j++) -      for(intk=0; k<nums[i-1];k++) the         if((state[i][j]&state[i-1][k]) = =0) +         { A           for(intq=0; q<nums[i-2];q++) the         { +             if((state[i-1][k]&state[i-2][Q]) = =0&& (state[i][j]&state[i-2][Q]) = =0) -             if(f[i][j][k]<f[i-1][k][q]+Cnts[i][j]) $f[i][j][k]=f[i-1][k][q]+Cnts[i][j]; $         } -     } -     Long Longans=0; the      for(intI=0; i<nums[n];i++) -       for(intj=0; j<nums[n-1];j++)Wuyi       if(ans<F[n][i][j]) theans=F[n][i][j]; -printf"%i64d\n", ans);

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POJ1185 Artillery Positions