[评测记录](https://www.luogu.com.cn/record/81438305)
by jiangmuran @ 2022-07-27 21:07:01
@[jiangmuran](/user/645451)
```
1-?=2
```
答案是-1，你的评测是3
by __BAI__ @ 2022-07-27 22:13:07
另外
```
?+1=2
```
你的答案是-1
by __BAI__ @ 2022-07-27 22:14:11
@[jiangmuran](/user/645451) 帮你改了，改的地方加了注释
```
#include <iostream>
using namespace std;
long long js(long long a,long long b,char op)
{
if(op=='+')
{
return a+b;
}
else
{
return a-b;
}
}
int main()
{
long long nums[3]={};
int flag,now=0;
char op;
char c;
while(cin >>c)
{
if (c>='0' && c<='9')
{
nums[now]=nums[now]*10+(c-'0');
}
else if(c=='+' || c=='-')
{
op=c;
now++;
}
else if (c=='=')
{
now++;
}
else if (c=='?')
{
flag=now;
}
}
if(flag == 0)
{
cout << js(nums[2],nums[1],op=='+'?'-':'+') << endl;//nums[2]与nums[1]换位置
}
else if(flag == 1)
{
if(op=='-')
cout << js(nums[0],nums[2],'-') << endl;//没想到什么比较简洁的，加多了个if
else
cout << js(nums[2],nums[0],'-') << endl;
}
else if(flag == 2)
{
cout << js(nums[0],nums[1],op) << endl;
}
}
```
by __BAI__ @ 2022-07-27 22:22:58
@[__INF__](/user/458493) 谢谢大佬指教
by jiangmuran @ 2022-07-28 10:29:31