UVA-1586 Molar mass

 1 #include <iostream>
 2 #include <stdlib.h>
 3 #include <string>
 4 #include <vector>
 5 #include <algorithm>
 6 #include <string.h>
 7 #include <stack>
 8 #include <unordered_map>
 9 #include <math.h>
10 #include <iomanip>
11 
12 using namespace std;
13 
14 vector<double> molar2MassList {12.01,1.008,16.00,14.01};
15 enum molarList {C,H,O,N};
16 
17 int main()
18 {
19     int T;
20     cin >> T;
21     while(T --)
22     {
23         string input;
24         cin >> input;
25         double result = 0;
26         for(int i = 0; i < input.size(); i ++)
27         {
28             enum molarList state;
29             double num = 0;
30             int digit = 0;
31             if(input[i]=='C')
32             {
33                 state = C;
34                 result += molar2MassList[state];
35             }
36             else if(input[i]=='H')
37             {
38                 state = H;
39                 result += molar2MassList[state];
40             }
41             else if(input[i]=='O')
42             {
43                 state = O;
44                 result += molar2MassList[state];
45             }
46             else if(input[i]=='N')
47             {
48                 state = N;
49                 result += molar2MassList[state];
50             }
51             else
52             {
53                 while(isdigit(input[i]))
54                 {
55                     num = pow(10,digit++) * num + (input[i++]-'0');
56                 }
57                 result += (num-1)*molar2MassList[state];
58                 i --;
59             }
60         }
61         cout << fixed << setprecision(3) << result << endl;
62     }
63     return 0;
64 }