1 #include <iostream> 2 #include <algorithm> 3 #include <cstring> 4 #include <cstdio> 5 #include <string> 6 #include <cmath> 7 8 #define Faster ios::sync_with_stdio(false),cin.tie(0) 9 #define Read freopen("in.txt","r",stdin),freopen("out.txt","w",stdout) 10 #define Close fclose(stdin),fclose(stdout) 11 const int maxn = 1e5 + 5; 12 using namespace std; 13 const int MOD = 1e9+7; 14 typedef long long ll; 15 int a[maxn]; 16 int dp[maxn][2]; 17 18 int dfs(int pos, int pre, int sta, bool limit){ 19 if(pos == -1) return 1; 20 if(!limit && dp[pos][sta] != -1) return dp[pos][sta]; 21 int up = limit? a[pos]:9; 22 int tmp = 0; 23 for(int i = 0;i <= up;i++){ 24 if(pre == 6 && i == 2) 25 continue; 26 if(i == 4) 27 continue; 28 tmp += dfs(pos-1, i, i == 6, limit && i == a[pos]); 29 } 30 if(!limit) dp[pos][sta] = tmp; 31 return tmp; 32 } 33 34 //从 1到x 的满足的数量 35 int solve(int x){ 36 int pos = 0; 37 while(x){ 38 a[pos++] = x%10; 39 x /= 10; 40 } 41 return dfs(pos-1, -1, 0, true); 42 } 43 44 int main(){ 45 Faster; 46 int l, r; 47 while(cin >> l >> r){ 48 if(l == 0 && r == 0) 49 break; 50 memset(dp, -1, sizeof dp); 51 int ans = solve(r) - solve(l-1); 52 cout << ans << endl; 53 } 54 return 0; 55 }
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