1 #include <iostream>
2 #include <string>
3 #include <math.h>
4 using namespace std;
5 const double Threshold = 1e-6;
6 const int CardsNumber = 4;
7 const int ResultValue = 24;
8 double number[CardsNumber];
9 string result[CardsNumber];
10 bool PointGame(int n)
11 {
12 if(n == 1)
13 {
14 if(fabs(number[0] - ResultValue) < Threshold)
15 {
16 cout << result[0] << endl;
17 return true;
18 }
19 else
20 {
21 return false;
22 }
23 }
24
25 for(int i = 0; i < n; i++)
26 {
27 for(int j = i +1 ; j < n; j++)
28 {
29 double a, b;
30 string expa, expb;
31 a = number[i];
32 b = number[j];
33 number[j] = number[n - 1];
34
35 expa = result[i];
36 expb = result[j];
37 result[j] = result[n-1];
38 number[i] = a + b;
39 result[i] = '(' + expa + '+' + expb + ')';
40 if(PointGame(n-1))
41 {
42 return true;
43 }
44 number[i] = a - b;
45 result[i] = '(' + expa + '-' + expb + ')';
46 if(PointGame(n-1))
47 {
48 return true;
49 }
50 number[i] = b - a;
51 result[i] = '(' + expb + '-' + expa + ')';
52 if(PointGame(n-1))
53 {
54 return true;
55 }
56 number[i] = a * b;
57 result[i] = '(' + expa + '*' + expb + ')';
58 if(PointGame(n-1))
59 {
60 return true;
61 }
62 if(b != 0)
63 {
64 number[i] = a / b;
65 result[i] = '(' + expa + '/' + expb + ')';
66 if(PointGame(n-1))
67 {
68 return true;
69 }
70 }
71
72 if(a != 0)
73 {
74 number[i] = b / a;
75 result[i] = '(' + expb + '/' + expa + ')';
76 if(PointGame(n-1))
77 {
78 return true;
79 }
80 }
81
82 number[i] = a;
83 number[j] = b;
84 result[i] = expa;
85 result[j] = expb;
86
87 }
88 }
89 return false;
90
91 }
92
93 void main()
94 {
95 int x;
96 for(int i =0; i< CardsNumber; i++)
97 {
98 cout << "the " << i << "the number: ";
99 cin >> x;
100 number[i] = x;
101 result[i] = (char)(x + '0');
102 }
103
104 if(PointGame(CardsNumber))
105 {
106 cout << "Success" << endl;
107
108 }
109 else
110 {
111 cout << "failure" << endl;
112 }
113
114
115 }
View Code
