#include 
#include 
using namespace std;
int n;
int dp[1010];
vectorv;
vectorv1;
pair backtrack[1010];

int rec(int i=0){
    if(i==n){
        backtrack[i] = make_pair(-1, -1);
        return 0;
    }

    if(dp[i]!=-1){
        return(dp[i]);
    }

    int result=2e9;
    int sam = rec(i+1)+v[i];
    int spoen = 2e9;
    if(i+1>n;

    for(int i=0; i>a;
        v.push_back(a);

        dp[i]=-1;
    }

    for(int j=0; j>b;
        v1.push_back(b);
    }

    rec(0);
    int at =0 ;
    while(at < n) {
        if(backtrack[at].second == 1) {
            cout << backtrack[at].first - 1 << " " << backtrack[at].first << endl;
        }
        at = backtrack[at].first;
    }



    return 0;
}