#include <stdio.h>
int is_alternating_pattern(int *mem, int k) {
int *curr=mem;
int exp=*curr;
for(int i=0;i<k;i++)
{if(*curr!=exp){return 0;}
exp=1-exp;
curr++;}
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;
}