#include <stdio.h>
#include <algorithm>
#define MAXN 250010
using namespace std;

int N, P;
int V[MAXN];
int memo[MAXN][2];

int dp(int idx, bool goup) {
    if (idx > N) return 0;
    if (V[idx] == V[idx+1]) return dp(idx+1, goup) + 1;

    if (memo[idx][goup] > -1) return memo[idx][goup];

    int best = 0;
    for (int i = idx+1; i <= N; i++) {
        if (goup && V[i] > V[idx]) {
            best = max(best, dp(i, !goup) + 1);
        }
        else if (!goup && V[i] < V[idx]) {
            best = max(best, dp(i, !goup) + 1);
        }

    }

    return memo[idx][goup] = best;
}

int main() {
    freopen("input.txt", "r", stdin);
    //freopen("output.txt", "w", stdout);
    scanf("%d%d", &N, &P);
    for (int i = 1; i <= N; i++) {
        scanf("%d", &V[i]);
    }

    for (int i = 0; i <= N; i++) {
        memo[i][0] = memo[i][1] = -1;
    }

    int res = dp(0, true);
    printf("%d\n", res);

    return 0;
}