Can anyone please tell me what's wrong with my code??

#include
#include
using namespace std;
int main()
{
int n;
cin>>n;
while(n–)
{
int n,i,j,k,a=0,b=0,c=0,x,y;
string str,st;
cin>>str>>st;
for(i=0;i<str.length();i++)
{
if((str[i]==‘b’ && st[i]!=‘o’) || (str[i]!=‘o’ && st[i]==‘b’) || (st[i]==‘b’ && str[i]==‘b’))
a++;
}
for(j=0;j<str.length();j++)
{
if((str[j]==‘o’ && st[j]!=‘b’) || (str[j]!=‘b’ && st[j]==‘o’) || (str[j]==‘o’ && st[j]==‘o’))
b++;
}
for(k=0;k<str.length();k++)
{
if((str[k]==‘b’ && st[k]==‘o’) || (str[k]==‘o’ && st[k]==‘b’))
c++;
}
x=a+c;
y=b+c;
if(a==2 && b==1)
cout<<“yes”<<endl;
else if(a==2 && y==1)
cout<<“yes”<<endl;
else if(x==2 && b==1)
cout<<“yes”<<endl;
else
cout<<“no”<<endl;

}
return 0;

}