freopen("magic.in","r",stdin);
    freopen("magic.out","w",stdout);
    //freopen("input.txt","r",stdin);
    //freopen("output.txt","w",stdout);
    int n;
    scanf("%d",&n);
    n++;
    int s[n],f[n];
    for(int i=0;i<n;i++){
        scanf("%d %d\n",&s[i],&f[i]);
    }
    bool al=0;
    int id1=0,id2=0;
    for(int i=0;i<n;i++){
        if(al)break;
        for(int j=i+1;j<ceil(1.0*n/2);j++){
            if(al)break;
            if(s[j]>f[i] || s[i]>f[j]){
                al=1;
                id1=i;
                id2=j;
            }
            if(s[n-j]>f[i] || s[i]>f[n-j]){
                al=1;
                id1=i;
                id2=n-j;
            }
        }
    }
    for(int i=0;i<n;i++){
        if(i!=id2){
            if(s[i]>f[id1] || s[id1]>f[i]){
                printf("%d",id1+1);
                return 0;
            }
        }
        if(i!=id1){
            if(s[i]>f[id2] || s[id2]>f[i]){
                printf("%d",id2+1);
                return 0;
            }
        }
    }
    printf("%d",id2+1);