[CQOI]涂色

a799091501的题解

#include<iostream>
#include<cstdio>
#include<cstring>
using namespace std;
const int maxn=1007;
int a[maxn],f[maxn][maxn];
int n,ans;
char k;
int main(){
    memset(f,0x7f,sizeof(f)); 
    while(cin>>k) a[++n]=k-64;
    for(int i=1;i<=n;i++) f[i][i]=1;
    for(int l=1;l<=n;l++){
        for(int i=1;i<=n;i++){
            int j=i+l;if(j>n) break;
            if(a[i]==a[j]){
                f[i][j]=min(f[i+1][j],f[i][j-1]);
                f[i][j]=min(f[i][j],f[i+1][j-1]+1);
            }
            for(int k=i;k<=j;k++) f[i][j]=min(f[i][j],f[i][k]+f[k+1][j]);
        } 
    }
    cout<<f[1][n]<<endl;
    return 0;
} 

这样是60分，但我不懂......

#include<iostream>
#include<cstdio>
using namespace std;
const int maxn=1007;
int a[maxn],b[maxn],f[maxn];
int n,ans;
char k;
int main(){
    while(cin>>k) a[++n]=k-64;
    for(int i=1;i<=n;i++){
        int j=n;
        if(a[i]!=b[i]){
            ans++;
            while(a[j]==b[j]) j--;
            for(int k=i;k<=j;k++) b[k]=a[i];
        }
    } 
    cout<<ans<<endl;
    return 0;
}