921

//921
#include <cstdio>

int main(void) {
    FILE* fin = fopen("input.txt", "r");
    FILE* fout = fopen("output.txt", "w");

    int a, b;
    fscanf(fin, "%d%d", &a, &b);
    fclose(fin);
    if (a > 0 || a < 0 && b % 2 == 0)
        fprintf(fout, "1\n");
    else if (a == 0)
        fprintf(fout, "0\n");
    else
        fprintf(fout, "-1\n");
    fclose(fout);
    return 0;
}