[luogu4158 SCOI2009] 粉刷匠(dp)

传送门

Solution

把状态都记上暴力转移即可

Code

//By Menteur_Hxy
#include <queue>
#include <cmath>
#include <cstdio>
#include <vector>
#include <cstring>
#include <cstdlib>
#include <iostream>
#include <algorithm>
#define Re register
#define Ms(a,b) memset(a,(b),sizeof(a))
#define Fo(i,a,b) for(Re int i=(a),_=(b);i<=_;i++)
#define Ro(i,a,b) for(Re int i=(b),_=(a);i>=_;i--)
using namespace std;
typedef long long LL;
typedef pair<int,int> PII;

inline LL read() {
	LL x=0,f=1;char c=getchar();
	while(!isdigit(c)) {if(c=='-')f=-f;c=getchar();}
	while(isdigit(c)) x=(x<<1)+(x<<3)+c-48,c=getchar();
	return x*f;
}

const int N=51;
int n,m,t,ans;
int f[N][N][N*N][2];
char s[N];

int main() {
	n=read(),m=read(),t=read();
	Fo(i,1,n) {
		scanf("%s",s+1);
		Fo(j,1,m) Fo(k,1,t) {
			if(j==1) {
				f[i][j][k][0]=max(f[i-1][m][k-1][0],f[i-1][m][k-1][1]);
				f[i][j][k][1]=f[i][j][k][0]+1;

			} else {
				if(s[j]==s[j-1]) {
					f[i][j][k][1]=max(f[i][j-1][k][1],f[i][j-1][k-1][0])+1;
					f[i][j][k][0]=max(f[i][j-1][k][0],f[i][j-1][k-1][1]);
				} else {
					f[i][j][k][1]=max(f[i][j-1][k-1][1],f[i][j-1][k][0])+1;
					f[i][j][k][0]=max(f[i][j-1][k-1][0],f[i][j-1][k][1]);
				}
			}
			ans=max(ans,max(f[i][j][k][0],f[i][j][k][1]));
		}
	}
	printf("%d",ans);
	return 0;
}