SPOJ Raone (Digital DP)

Raone-ra-one NumbersNo Tags

In the War between good and evil. Ra-one is on the evil side and G-one on the good side.

Ra-one is fond of destroying cities and its g-one ' s duty to protect them.

Ra-one loves to destroy cities whose Zip Code have special properties. He says he loves to destroy cities which has ra-one numbers as their ZIp Code.

Any number was ra-one if the difference between Sum of digits at even location and Sum of digits at odd location is one (1) .. For eg ... for 234563 is ra-one number

Digits at odd location was 3,5,3 (unit place was location 1)

Digits at even location is 2,4,6

Diff = (2+4+6)-(3+5+3) =12-11 = 1.

And 123456 is not ra-one number

diff = (5+3+1)-(2+4+6) = 4

G-one knows this is about the Ra-one and wants to the deploy his Army members in those cities. 1 Army member'll be deployed.

G-one knows the range of Zip-codes where Ra-one might attack & needs your help to find out what many Army members he NE Eds.

Can you help him?

Input

First line'll has only one integer ' t ' of zip-code ranges. It's followed by T lines

Each line from 2nd line cotains 2 "from" and "to". These indicate the range of ZIP codes where Ra-one might attack. (From and to is included in the range)

Output

A single number for each test case telling the many Army members G-one needs to deploy.

Each number should is on separate lines

Example

 
Input: 2
1 10
10 100

 Output: 1
9
explanation:
for 1st test case the only number is 10
for 2nd test case numbers are 10,21,32,43,54,65,76,87,98  NOTE: t will be less than 100
from and to will be between 0 and 10^8 inclusive 

Links: http://www.spoj.com/problems/RAONE/en/
Test instructions: The number of points in which an interval even position minus an odd position is one

IDEA: Digital DP

#include<iostream>
#include<cstdio>
#include<cstring>
#include<algorithm>
#include<cmath>
#include<queue>
#include<stack>
#include<vector>
#include<set>
#include<map>

#define L(x) (x<<1)
#define R(x) (x<<1|1)
#define MID(x,y) ((x+y)>>1)

#define bug printf("hihi\n")

#define eps 1e-8

using namespace std;


#define INF 0x3f3f3f3f
#define N  100

int dp[10][100][100];
int bit[20];

int dfs(int pos,int le,int ri,bool bound)
{
    if(pos==0) return ri-le==1 ? 1:0;
    if(!bound&&dp[pos][le][ri]>=0) return dp[pos][le][ri];
    int up=bound ? bit[pos]:9;
    int ans=0;
    for(int i=0;i<=up;i++)
    {
        if(pos&1)
            ans+=dfs(pos-1,le+i,ri,bound&&i==up);
        else
            ans+=dfs(pos-1,le,ri+i,bound&&i==up);
    }
    if(!bound) dp[pos][le][ri]=ans;
    return ans;
}

int solve(int x)
{
    int i,j;
    int len=0;
    while(x)
    {
        bit[++len]=x%10;
        x/=10;
    }
    return dfs(len,0,0,true);
}

int main()
{
   int i,j;
   memset(dp,-1,sizeof(dp));
   int t;
   scanf("%d",&t);
   int le,ri;
   while(t--)
   {
       scanf("%d%d",&le,&ri);
       printf("%d\n",solve(ri)-solve(le-1));
   }
   return 0;
}

Raone-ra-one Numbers No Tags

In the War between good and evil. Ra-one is on the evil side and G-one on the good side.

Ra-one is fond of destroying cities and its g-one ' s duty to protect them.

Ra-one loves to destroy cities whose Zip Code have special properties. He says he loves to destroy cities which has ra-one numbers as their ZIp Code.

Any number was ra-one if the difference between Sum of digits at even location and Sum of digits at odd location is one (1) .. For eg ... for 234563 is ra-one number

Digits at odd location was 3,5,3 (unit place was location 1)

Digits at even location is 2,4,6

Diff = (2+4+6)-(3+5+3) =12-11 = 1.

And 123456 is not ra-one number

diff = (5+3+1)-(2+4+6) = 4

G-one knows this is about the Ra-one and wants to the deploy his Army members in those cities. 1 Army member'll be deployed.

G-one knows the range of Zip-codes where Ra-one might attack & needs your help to find out what many Army members he NE Eds.

Can you help him?

Input

First line'll has only one integer ' t ' of zip-code ranges. It's followed by T lines

Each line from 2nd line cotains 2 "from" and "to". These indicate the range of ZIP codes where Ra-one might attack. (From and to is included in the range)

Output

A single number for each test case telling the many Army members G-one needs to deploy.

Each number should is on separate lines

Example

 Input:
Input: 2
1 10
10 100

 Output: 1
9
explanation:
for 1st test case the only number is 10
for 2nd test case numbers are 10,21,32,43,54,65,76,87,98  NOTE: t will be less than 100
from and to will be between 0 and 10^8 inclusive

Copyright NOTICE: This article for Bo Master original article, without Bo Master permission not reproduced.

SPOJ Raone (Digital DP)