#include <stdio.h>

int n, m, w[3000];
int dp[3001][4];

int max(int a, int b) { return (a > b ? a : b); }

int main(void) {
	scanf("%d%d", &n, &m);
	
	if(m < 2) { printf("0\n"); return 0; }
	
	int i, j;
	for(i = 0; i < n; i++) {
		scanf("%d", &w[i]);
	}
	
	dp[0][3] = w[0];
	for(i = 2; i < n; i++) {
	for(j = i - 1; 0 <= j; j--) {
		int a = dp[j - 1][3], b = dp[j - 1][1];
		int w1 = w[i - 1], w2 = (i == n - 1 ? w[i] : 0);
		if(j == i - 1) {
			dp[j][3] = a + w1 + w2;
			dp[j][2] = a;
			dp[j][1] = b + w1;
			dp[j][0] = b;
		} else if(j == 0) {
			dp[0][3] = w2;
		} else {
			dp[j][3] = max(dp[j][2], a + w1) + w2;
			dp[j][2] = max(dp[j][2], a);
			dp[j][1] = max(dp[j][0], b + w1);
			dp[j][0] = max(dp[j][0], b);
		}
	}
	}
	
	printf("%d\n", max( max(dp[m][0], dp[m - 1][1]), max(dp[m - 1][2], dp[m - 2][3]) ) );
	
	return 0;
}