感觉。。。好像。。。没毛病？

#include<bits/stdc++.h>
using namespace std;
int main() {
	freopen("P1957_2.in","r",stdin);
	int n,mi=1,xb;
	string c="",x="",x1="",x2="";
	cin>>n;
	for(int i=0; i<n; i++) {
		stringstream ss,sa,sc;
		cin>>c;
		if(c[0]>='a'&&c[0]<='c') {
			xb=c[0]-'a';
			switch(xb) {
				case 0:
					cin>>x>>x1;
					int a,b,m;
					ss<<x;
					ss>>a;
					sa<<x1;
					sa>>b;
					m=a+b;
					sc<<m;
					x2=sc.str();
					cout<<x<<'+'<<x1<<'='<<x2<<endl<<x2.size()+2+x.size()+x1.size()<<endl;
					break;
				case 1:
					cin>>x>>x1;
					ss<<x;
					ss>>a;
					sa<<x1;
					sa>>b;
					m=a-b;
					sc<<m;
					x2=sc.str();
					cout<<x<<'-'<<x1<<'='<<x2<<endl<<x2.size()+2+x.size()+x1.size()<<endl;
					break;
				case 2:
					cin>>x>>x1;
					ss<<x;
					ss>>a;
					sa<<x1;
					sa>>b;
					m=a*b;
					sc<<m;
					x2=sc.str();
					cout<<x<<'*'<<x1<<'='<<x2<<endl<<x2.size()+2+x.size()+x1.size()<<endl;
					break;
			}
		} else
			switch(xb) {
				case 0:
					cin>>x;
					int a,b,m;
					ss<<c;
					ss>>a;
					sa<<x;
					sa>>b;
					m=a+b;
					sc<<m;
					x2=sc.str();
					cout<<c<<'+'<<x<<'='<<x2<<endl<<x2.size()+2+x.size()+c.size()<<endl;
					break;
				case 1:
					cin>>x;
					ss<<c;
					ss>>a;
					sa<<x;
					sa>>b;
					m=a-b;
					sc<<m;
					x2=sc.str();
					cout<<c<<'-'<<x<<'='<<x2<<endl<<x2.size()+2+x.size()+c.size()<<endl;
					break;
				case 2:
					cin>>x>>x1;
					ss<<x;
					ss>>a;
					sa<<x1;
					sa>>b;
					m=a*b;
					sc<<m;
					x2=sc.str();
					cout<<x<<'*'<<x1<<'='<<x2<<endl<<x2.size()+2+x.size()+x1.size()<<endl;
					break;
			}
	}
}