NYOJ740

#include<stdio.h>
#include<string.h>
#include<math.h>

int dp[10001][6][6];
int a[10001];
int cost[6][6]={
{1,2,2,2,2},
{0,1,3,4,3},
{0,3,1,3,4},
{0,4,3,1,3},
{0,3,4,3,1}
};

int main()

{
    int i,j,k,n,ans,x,y,t;
    while(scanf("%d",&t)&&t!=0)
    {
        a[1] = t;
        for(n = 2;;n++)
        {
            scanf("%d",&a[n]);
            if(!a[n])
            {
                break;
            }
        }
        for(i = 0;i <= n;i++)
            for(j = 0;j < 5;j++)
                for(k = 0;k < 5;k++)
                    dp[i][j][k] = 100000005;
        dp[0][0][0] = 0;
        ans = 100000005;
        for(i = 1;i < n;i++)
        {
            for(j = 0;j < 5;j++) //先确定一只脚不动
            {
                if(j == a[i])continue;
                x = y = 100000005;
                for(k = 0;k < 5;k++)  //左脚动
                {
                    if(k != j||k + j == 0)
                    {
                        if(x > dp[i - 1][k][j] + cost[k][a[i]])
                        {
                            x = dp[i - 1][k][j] + cost[k][a[i]];
                        }
                    }
                }
                for(k = 0;k < 5;k++)  //右脚动
                {
                    if(k != j||k + j == 0)
                    {
                        if(y > dp[i - 1][j][k] + cost[k][a[i]])
                        {
                            y = dp[i - 1][j][k] + cost[k][a[i]];
                        }
                    }
                }
                if(x > y)x = y;
                dp[i][a[i]][j] = dp[i][j][a[i]] = x;   //左脚和右脚是可以相互转换的
                if(ans > dp[n - 1][j][a[i]])ans = dp[n - 1][j][a[i]];
            }
        }
        printf("%d\n",ans);
    }
    return 0;
}