[HDOJ3555]Bomb（数位DP）

题目链接：http://acm.hdu.edu.cn/showproblem.php?pid=3555

同理不要62，这回是要求带49的数，那么先求出不带49的，再减去。

 1 #include <bits/stdc++.h>
 2 using namespace std;
 3 #define fr first
 4 #define sc second
 5 #define cl clear
 6 #define BUG puts("here!!!")
 7 #define W(a) while(a--)
 8 #define pb(a) push_back(a)
 9 #define Rint(a) scanf("%d", &a)
10 #define Rll(a) scanf("%I64d", &a)
11 #define Rs(a) scanf("%s", a)
12 #define Cin(a) cin >> a
13 #define FRead() freopen("in", "r", stdin)
14 #define FWrite() freopen("out", "w", stdout)
15 #define Rep(i, len) for(int i = 0; i < (len); i++)
16 #define For(i, a, len) for(int i = (a); i < (len); i++)
17 #define Cls(a) memset((a), 0, sizeof(a))
18 #define Clr(a, x) memset((a), (x), sizeof(a))
19 #define Full(a) memset((a), 0x7f7f7f, sizeof(a))
20 #define lrt rt << 1
21 #define rrt rt << 1 | 1
22 #define pi 3.14159265359
23 #define RT return
24 #define lowbit(x) x & (-x)
25 #define onecnt(x) __builtin_popcount(x)
26 typedef long long LL;
27 typedef long double LD;
28 typedef unsigned long long ULL;
29 typedef pair<int, int> pii;
30 typedef pair<string, int> psi;
31 typedef pair<LL, LL> pll;
32 typedef map<string, int> msi;
33 typedef vector<int> vi;
34 typedef vector<LL> vl;
35 typedef vector<vl> vvl;
36 typedef vector<bool> vb;
37
38 const int maxn = 25;
39
40 LL digit[maxn];
41 LL dp[maxn][2];
42
43 LL dfs(int l, bool num, bool jud) {
44   if(l == 0) return dp[l][num] = 1;
45   if(!jud && ~dp[l][num]) return dp[l][num];
46   LL ret = 0;
47   int nex = jud ? digit[l] : 9;
48   Rep(i, nex+1) {
49     if(num && i == 9) continue;
50     ret += dfs(l-1, i==4, jud&&i==nex);
51   }
52   if(!jud) dp[l][num] = ret;
53   return ret;
54 }
55
56 LL f(LL num) {
57   int pos = 0;
58   while(num) {
59     digit[++pos] = num % 10;
60     num /= 10;
61   }
62   return dfs(pos, false, true);
63 }
64
65 LL n;
66
67 signed main() {
68   //FRead();
69   Clr(dp, -1);
70   int T;
71   Rint(T);
72   W(T) {
73     cin >> n;
74     cout << n - f(n) + 1 << endl;
75   }
76   RT 0;
77 }