C++問題

#include<iostream>
#include<cstdlib>
using namespace std;
union mydata
{
char name[15];
char number[7];;
}teacher;
int main(void)
{
char k;
cout<<"請輸入姓名:";
cin.getline(teacher.name,15);
cout<<"請輸入代號:";
cin.getline(teacher.number,7);
do{
cout<<"請問您的性別 (1)男性 (2)女性: ";
cin>>k;
}while((k>50)||(k<49));
switch(k)
{
case '1':
char m;
cout<<"是否役畢? (1)YES (2)NO ";
cin>>m;
if(m==49){
cout<<"姓名:"<<teacher.name<<endl;
cout<<"代號"<<teacher.number<<endl;
cout<<"男性"<<endl;
cout<<"役畢"<<endl;
}
if(m==50){
cout<<"姓名:"<<teacher.name<<endl;
cout<<"代號"<<teacher.number<<endl;
cout<<"男性"<<endl;
cout<<"未役"<<endl;
}
break;
case '2':
int h;
cout<<"打字速度?";
cin>>h;
cout<<"姓名:"<<teacher.name<<endl;
cout<<"代號"<<teacher.number<<endl;
cout<<"女性"<<endl;
cout<<"打字速度"<<h<<"字"<<endl;
break;
}




system("pause");
return 0;
}

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真奇怪!!一直在姓名的地方出錯!!
有誰能幫我除錯一下
小弟不才這麼簡單的東西都不會