LightOj_1364 Expected Cards

  1 #include <cmath>
  2 #include <cstdio>
  3 #include <cstring>
  4 #include <cstdlib>
  5 #include <ctime>
  6 #include <set>
  7 #include <map>
  8 #include <list>
  9 #include <queue>
 10 #include <string>
 11 #include <vector>
 12 #include <fstream>
 13 #include <iterator>
 14 #include <iostream>
 15 #include <algorithm>
 16 using namespace std;
 17 #define LL long long
 18 #define INF 0x3f3f3f3f
 19 #define MOD 1000000007
 20 #define eps 1e-6
 21 #define MAXN 16
 22 #define MAXM 82
 23 #define dd cout<<"debug"<<endl
 24 #define p(x) printf("%d\n", x)
 25 #define pd(x) printf("%.7lf\n", x)
 26 #define k(x) printf("Case %d: ", ++x)
 27 #define s(x) scanf("%d", &x)
 28 #define sd(x) scanf("%lf", &x)
 29 #define mes(x, d) memset(x, d, sizeof(x))
 30 #define do(i, x) for(i = 0; i < x; i ++)
 31 int C, D, H, S;
 32 double dp[MAXN][MAXN][MAXN][MAXN][MAXM];
 33 void init()
 34 {
 35     int i, j, k, m, l;
 36     do(i, MAXN)
 37         do(j, MAXN)
 38             do(k, MAXN)
 39                 do(m, MAXN)
 40                     do(l, MAXM)
 41                         dp[i][j][k][m][l] = -1.0;
 42 }
 43 bool is_ok(int c, int d, int h, int s, int j)
 44 {
 45     int bit[4] = {0, 0, 0, 0};
 46     int cnt = 0;
 47     while(j)
 48     {
 49         bit[cnt ++] = j % 3;
 50         j /= 3;
 51     }
 52     c += bit[0];
 53     d += bit[1];
 54     h += bit[2];
 55     s += bit[3];
 56     if(c >= C && d >= D && h >= H && s >= S)
 57         return true;
 58     return false;
 59 }
 60 double dfs(int c, int d, int h, int s, int j)
 61 {
 62     double &res = dp[c][d][h][s][j];
 63     if(res != -1.0)
 64         return res;
 65     if(is_ok(c, d, h, s, j))
 66         return res = 0.0;
 67     res = 0.0;
 68     int bit[4] = {0, 0, 0, 0};
 69     int num = 0;
 70     int jj = j;
 71     for(int i = 0; i < 4; i ++)
 72     {
 73         bit[i] = j % 3;
 74         j /= 3;
 75         num += bit[i];
 76     }
 77     int sum = 54 - (c + d + h + s + num);
 78     if(c < 13 && sum)
 79     {
 80         double p = (13 - c) * 1.0 / sum;
 81         res += (dfs(c + 1, d, h, s, jj) + 1) * p;
 82     }
 83     if(d < 13 && sum)
 84     {
 85         double p = (13 - d) * 1.0 / sum;
 86         res += (dfs(c, d + 1, h, s, jj) + 1) * p;
 87     }
 88     if(h < 13 && sum)
 89     {
 90         double p = (13 - h) * 1.0 / sum;
 91         res += (dfs(c, d, h + 1, s, jj) + 1) * p;
 92     }
 93     if(s < 13 && sum)
 94     {
 95         double p = (13 - s) * 1.0 / sum;
 96         res += (dfs(c, d, h, s + 1, jj) + 1) * p;
 97     }
 98     if(num < 2 && sum)
 99     {
100         double p = (2 - num) * 1.0 / sum;
101         int cnt = bit[0] + 1 + bit[1] * 3 + bit[2] * 9 + bit[3] * 27;
102         double temp = dfs(c, d, h, s, cnt);
103 
104         cnt = bit[0] + (bit[1] + 1) * 3 + bit[2] * 9 + bit[3] * 27;
105         temp = min(temp, dfs(c, d, h, s, cnt));
106 
107         cnt = bit[0] + bit[1] * 3 + (bit[2] + 1) * 9 + bit[3] * 27;
108         temp = min(temp, dfs(c, d, h, s, cnt));
109 
110         cnt = bit[0] + bit[1] * 3 + bit[2] * 9 + (bit[3] + 1) * 27;
111         temp = min(temp, dfs(c, d, h, s, cnt));
112 
113         res += (temp + 1.0) * p;
114     }
115     return res;
116 }
117 
118 int main()
119 {
120     int T;
121     int kcase = 0;
122     scanf("%d", &T);
123     while(T --)
124     {
125         scanf("%d %d %d %d", &C, &D, &H, &S);
126         int x = 0;
127         init();
128         x = (C > 13? C - 13 : 0) + (D > 13? D - 13 : 0) + (H > 13? H - 13 : 0) + (S > 13? S - 13 : 0);
129         if(x > 2)
130             printf("Case %d: -1\n", ++ kcase);
131         else 
132         {
133             double ans = dfs(0, 0, 0, 0, 0);
134             printf("Case %d: %.7lf\n", ++ kcase, ans);
135         } 
136     }
137     return 0;
138 }