#include <stdio.h>
int is_alternating_pattern(int *mem, int k) {
// Write your pointer logic here
int* p1 = mem;
int* p2 = mem+1;
if(k<3)
return 0;
while((p1+2)<mem+k && (p2+2)<mem+k){
if(*p1 != *(p1+2))
return 0;
if(k>=4 && *p2 != *(p2+2))
return 0;
p1+=2;
p2+=2;
}
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;
}