uestc250windy数数位dp

#include <cstdio>

#include <cstring>

#include <cmath>

#include <algorithm>

#include <climits>

#include <string>

#include <iostream>

#include <map>

#include <cstdlib>

#include <list>

#include <set>

#include <queue>

#include <stack>

using namespace std;



int dp[100][100][2];

int up[1000];

int ab(int x)

{

    return x>0? x:-x;

}



int dfs(int pos,int top,int first,int flag)

{

    if(pos<=0) return first==1;

    if(first&&!flag&&~dp[pos][top][first]) return dp[pos][top][first];

    int limit = flag? up[pos]: 9,ret=0;

    for(int i= 0;i<=limit;i++){ 

        int t= ab(top-i);  

        if(t>=2||!first) ret+=dfs(pos-1,i,first||i,flag&&(i==limit)); //这个判断是海哥告诉的，非常吊，自己品味。

    }

    return  flag? ret: dp[pos][top][first] = ret;

}

int solve(int x)

{

    int len=0;

    while(x){

        up[++len]=x%10;

        x/=10;

    }

    return dfs(len,100,0,1);

}

int main()

{

    memset(dp,-1,sizeof(dp));

    int n,m;

    while(scanf("%d%d",&n,&m)!=EOF){

        cout<<solve(m) - solve(n-1) <<endl;

    }

    return 0;

}