题解

#include<bits/stdc++.h>
using namespace std;
int t,x,y,mod;
long long book[100][100];
int rem(int x,int y){
    if(book[x][y]==-1){
        return -1;
    }
    if(book[x][y]){
        return book[x][y];
    }
    book[x][y]=-1;
    if(!x){
        return book[x][y]=1;
    }
    if(!y){
        return book[x][y]=2;
    }
    int num=(x+y)%mod;
    return book[x][y]=rem(num,(num%mod+y)%mod);
}
int main(){
    cin>>t>>mod;
    for(int i=0;i<t;i++){
        memset(book,0,sizeof(book));
        cin>>x>>y;
        int ans=rem(x,y);
        if(ans==-1){
            cout<<"error"<<endl;
        }
        else if(ans==1){
            cout<<"1"<<endl;
        }
        else{
            cout<<"2"<<endl;
        }
    }
    return 0;
}