#include <stdio.h>

int main()
{
        int N;
        int top;
        int num;
        int sum;
        int prev;
        int tmp;

        scanf("%d", &N );

        prev = 0;
        top = N/2;
        sum = 0;

        while( 1 ) {
                printf("? %d\n", top ); fflush( stdout );
                scanf( "%d", &num );
                if( num == -1 ) {
                        return(0);
                }
                if( sum + num == N / 2 ) {
                        if( top == N ) {
                                printf("! %d %d\n", 2, N-1  );fflush( stdout );
                                return 0;
                        }

                        printf("! %d %d\n", 1, top );fflush( stdout );
                        return 0;
                }
                if( sum + num < N /2 ) {
                        top = ( top + N ) /2 + ( top + N ) % 2;
                }
                else {
                        tmp = top;
                        top = ( top + prev ) / 2 + ( top + prev ) %2;
                        prev = top;
                }
        }
        return 0;
}