C++用Beep函数来弹钢琴

```
 1 #include<windows.h>
 2 #include<iostream>
 3 #include<string>
 4 using namespace std;
 5 int stop=500;
 6 int getFreq(char key){
 7     int freq=0;
 8     switch(key){
 9         //中音区 
10         case 'a':freq=262;break;
11         case 's':freq=294;break;
12         case 'd':freq=330;break;
13         case 'f':freq=349;break;
14         case 'g':freq=392;break;
15         case 'h':freq=440;break;
16         case 'j':freq=494;break;
17         //低音区 
18         case 'z':freq=131;break;
19         case 'x':freq=147;break;
20         case 'c':freq=165;break;
21         case 'v':freq=175;break;
22         case 'b':freq=195;break;
23         case 'n':freq=220;break;
24         case 'm':freq=247;break;
25     }
26     return freq;
27 }
28 string twoTiger="asdaasdadfg dfg g_h_g_f_dag_h_g_f_dasba sba";
29 string aiHe="asddghhaadsaasd  asddghhaadsaama";
30 int main(){
31     string score=aiHe;
32     
33     for(int i=0;i<score.length();i++){
34         if(score[i]==' '){
35             Sleep(stop);//四分休止符 
36         }else if(score[i]=='_'){
37             //do nothing
38         }else{
39             if((i+1)==score.length()){//是否到末尾 
40                 Beep(getFreq(score[i]),stop);
41             }else{
42                 if(score[i+1]=='_'){//是否是八分音符 
43                     Beep(getFreq(score[i]),stop/2);
44                 }else{
45                     Beep(getFreq(score[i]),stop);//四分音符 
46                 }
47             }
48             
49         }
50     }
51     return 0;
52 }
```