#include <stdio.h>
int is_alternating_pattern(int *mem, int k) {
// Write your pointer logic here
for (int i = 0; i < k - 1; i++) {
// Note: this only works with 0-1 patterns
if ((*mem ^ *(mem + 1)) == 0) {
return 0;
}
++mem;
}
return 1;
}
int main() {
int n, k, arr[100];
scanf("%d %d", &n, &k);
for (int i = 0; i < n; i++) {
scanf("%d", &arr[i]);
}
int res = is_alternating_pattern(arr, k);
printf("%d", res);
return 0;
}