UESTC 250 数位DP

来源：互联网发布：mac os x 安装软件编辑：程序博客网时间：2024/06/10 01:12

点击打开链接

题意：中文

思路：加个flag标记一下是不是前导为0就可以了

#include <math.h>#include <stdio.h>#include <stdlib.h>#include <string.h>#include <iostream>#include <algorithm>using namespace std;typedef long long ll;typedef unsigned long long ull;const int inf=0x3f3f3f3f;const ll INF=0x3f3f3f3f3f3f3f3fll;const int maxn=5010;int dig[30];ll dp[20][10][2];ll dfs(int pos,int lim,int pre,int flag){    if(pos<0){        if(flag) return 0;        else return 1;    }    if(!lim&&dp[pos][pre][flag]!=-1) return dp[pos][pre][flag];    int las=lim?dig[pos]:9;    ll ret=0;    for(int i=0;i<=las;i++){        if(flag==1){            if(i==0) ret+=dfs(pos-1,lim&&(i==las),0,1);            else ret+=dfs(pos-1,lim&&(i==las),i,0);        }else if(abs(i-pre)>=2) ret+=dfs(pos-1,lim&&(i==las),i,0);    }    if(!lim) dp[pos][pre][flag]=ret;    return ret;}ll slove(ll n){    if(n==0) return 0;    int len=0;    while(n){        dig[len++]=n%10;        n/=10;    }    return dfs(len-1,1,0,1);}int main(){    memset(dp,-1,sizeof(dp));    ll n,m;    while(scanf("%lld%lld",&n,&m)!=-1){        printf("%lld\n",slove(m)-slove(n-1));    }    return 0;}

0 0