相差一个长度的不知道怎么写

#include <bits/stdc++.h>
#define int long long
#define endl '\n'
using namespace std;
int n,cnt=0;
string a,b;
signed main()
{
    cin.tie(0),cout.tie(0);
    cin>>n;
    for(int i=1;i<=n;i++){
        cin>>a>>b;
    }
    for(int i=0;i<n;i++){
        if(a.size()<b.size()){
            swap(a,b);
        }
        if(a.size()-b.size()>1){
            cout<<"not similar"<<endl;
        }
        if(a.size()==b.size()){
            for(int i=1;i<=n;i++){
                if(a[i]!=b[i]){
                    cnt++;
                }
            }
            if(cnt>=2) cout<<"not similar"<<endl;
            else cout<<"similar"<<endl;
        }
        if(a.size()-b.size()==1){
            int f=0;
            for(int i=0;i<n;i++){
                if(a[i]==b[i]||a[i-1]==b[i]){
                    f=1;
                }
            }
            if(f==1){
                cout<<"similar"<<endl;
            }
            else cout<<"not similar"<<endl;
        }
    }
    return 0;
}