uva 1586 Molar mass(Uva-1586)

这题做的相当的复杂。。。之前做的现在应该能简单一点了写的。

我的代码：

#include <bits/stdc++.h>
using namespace std;
main()
{
    int a;
    cin>>a;
    while(a--)
    {
        string b="";
        cin>>b;
        stringstream stream;
        int sumc,sumh,sumo,sumn;
        sumc=sumh=sumo=sumn=;
        int c,h,o,n,f;
        c=h=o=n=;f=;
        string str="";
        for(int i=;i<b.size()+;i++)
        {
            if(isalpha(b[i])&&isalpha(b[i+])||isalpha(b[i])&&!b[i+])
            {
                if(b[i]=='C')
                sumc+=;
                if(b[i]=='H')
                sumh+=;
                if(b[i]=='O')
                sumo+=;
                if(b[i]=='N')
                sumn+=;
            }
            else if(isdigit(b[i])&&f)
            {
                if(b[i-]=='C')
                {
                    str+=b[i];c=;f=;
                }
                if(b[i-]=='H')
                {
                    str+=b[i];h=;f=;
                }
                if(b[i-]=='O')
                {
                    str+=b[i];o=;f=;
                }
                if(b[i-]=='N')
                {
                    str+=b[i];n=;f=;
                }
            }
            else if(c&&!f)
            {
                if(isalpha(b[i])||!b[i])
                {
                    int num=;
                    f=;c=;
                    stream<<str;
                    stream>>num;
                    sumc+=num;
                    stream.clear();
                    str="";
                }
                else
                str+=b[i];
            }
            else if(h&&!f)
            {
                if(isalpha(b[i])||!b[i])
                {
                    int num=;
                    f=;h=;
                    stream<<str;
                    stream>>num;
                    sumh+=num;
                    stream.clear();
                    str="";
                }
                else
                str+=b[i];
            }
            else if(o&&!f)
            {
                if(isalpha(b[i])||!b[i])
                {
                    int num=;
                    f=;o=;
                    stream<<str;
                    stream>>num;
                    sumo+=num;
                    stream.clear();
                    str="";
                }
                else
                str+=b[i];
            }
            else if(n&&!f)
            {
                if(isalpha(b[i])||!b[i])
                {
                    int num=;
                    f=;n=;
                    stream<<str;
                    stream>>num;
                    sumn+=num;
                    stream.clear();
                    str="";
                }
                else
                str+=b[i];
            }
        }
        double sum=;
        sum=sumc*12.01+sumh*1.008+sumo*16.00+sumn*14.01;
        printf("%.3lf\n",sum);
    }
}