tjut 5898

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#include<set>  
#include<map>  
#include<ctime>  
#include<cmath>  
#include<stack>  
#include<queue>  
#include<cstdio>  
#include<string>  
#include<cstring>  
#include<iostream>  
#include<algorithm>  
#include<functional>  
typedef long long LL;  
using namespace std;  
#define inf 0x3f3f3f3f  
#define maxn 55  
typedef long long LL;  
int num[25];  
LL dp[25][5];  
LL dfs(int pos, int limit, int status){  
    if (pos < 1){  
        if (status == 2 || status == 3)  
            return 1;  
        else  
            return 0;  
    }  
    if (!limit&&~dp[pos][status])  
        return dp[pos][status];  
    int end = limit ? num[pos] : 9;  
    LL ans = 0;  
    for (int i = 0; i <= end; i++){  
        if (!status){  
            if (!i){  
                ans += dfs(pos - 1, 0, 0);  
            }  
            else if (i & 1){  
                ans += dfs(pos - 1, limit&&i == end, 1);  
            }  
            else{  
                ans += dfs(pos - 1, limit&&i == end, 3);  
            }  
        }  
        else{  
            if (status == 1){  
                if (i & 1){  
                    ans += dfs(pos - 1, limit&&i == end, 2);  
                }  
            }  
            else if (status == 2){  
                if (i & 1){  
                    ans += dfs(pos - 1, limit&&i == end, 1);  
                }  
                else{  
                    ans += dfs(pos - 1, limit&&i == end, 3);  
                }  
            }  
            else if (status == 3){  
                if (i & 1){  
                    ans += dfs(pos - 1, limit&&i == end, 1);  
                }  
                else{  
                    ans += dfs(pos - 1, limit&&i == end, 4);  
                }  
            }  
            else{  
                if (!(i & 1)){  
                    ans += dfs(pos - 1, limit&&i == end, 3);  
                }  
            }  
        }  
    }  
    dp[pos][status] = ans;  
    return ans;  
}  
LL solve(LL x){  
    memset(dp, -1, sizeof(dp));  
    int len = 0;  
    while (x){  
        num[++len] = x % 10;  
        x /= 10;  
    }  
    return dfs(len, 1, 0);  
}  
int main(){  
    int t;  
    scanf("%d", &t);  
    for (int tcase = 1; tcase <= t; tcase++){  
        LL l, r;  
        scanf("%lld%lld", &l, &r);  
        printf("Case #%d: %lld\n", tcase, solve(r) - solve(l - 1));  
    }  
}