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| 1 | +```java |
| 2 | +import java.io.*; |
| 3 | +import java.util.*; |
| 4 | + |
| 5 | +public class Main { |
| 6 | + |
| 7 | + static int NEG_INF = Integer.MIN_VALUE / 4; |
| 8 | + static int size,groupCnt; |
| 9 | + static int[] a; |
| 10 | + |
| 11 | + public static void main(String[] args) throws Exception { |
| 12 | + init(); |
| 13 | + process(); |
| 14 | + |
| 15 | + } |
| 16 | + |
| 17 | + public static void init() throws IOException { |
| 18 | + BufferedReader br = new BufferedReader(new InputStreamReader(System.in)); |
| 19 | + StringTokenizer st = new StringTokenizer(br.readLine()); |
| 20 | + size = Integer.parseInt(st.nextToken()); |
| 21 | + groupCnt = Integer.parseInt(st.nextToken()); |
| 22 | + |
| 23 | + a = new int[size + 1]; |
| 24 | + st = new StringTokenizer(br.readLine()); |
| 25 | + for (int i = 1; i <= size; i++) a[i] = Integer.parseInt(st.nextToken()); |
| 26 | + } |
| 27 | + |
| 28 | + public static void process(){ |
| 29 | + |
| 30 | + int[] prefixSum = new int[size + 1]; |
| 31 | + for (int i = 1; i <= size; i++) prefixSum[i] = prefixSum[i - 1] + a[i]; |
| 32 | + |
| 33 | + |
| 34 | + int[][] dp = new int[size + 1][groupCnt + 1]; |
| 35 | + for (int i = 0; i <= size; i++) { |
| 36 | + Arrays.fill(dp[i], NEG_INF); |
| 37 | + dp[i][0] = 0; |
| 38 | + } |
| 39 | + dp[0][0] = 0; |
| 40 | + |
| 41 | + // dp[i][j] = max(dp[i-1][j], max_s(dp[s-1][j-1] + (ps[i]-ps[s-1]))) |
| 42 | + // = max(dp[i-1][j], (max_s(dp[s-1][j-1] - ps[s-1])) + ps[i]) |
| 43 | + for (int j = 1; j <= groupCnt; j++) { |
| 44 | + int best = NEG_INF; |
| 45 | + for (int i = 1; i <= size; i++) { |
| 46 | + best = Math.max(best, dp[i - 1][j - 1] - prefixSum[i - 1]); |
| 47 | + |
| 48 | + dp[i][j] = Math.max(dp[i][j], dp[i - 1][j]); |
| 49 | + |
| 50 | + if (best > NEG_INF) { |
| 51 | + dp[i][j] = Math.max(dp[i][j], best + prefixSum[i]); |
| 52 | + } |
| 53 | + } |
| 54 | + } |
| 55 | + |
| 56 | + System.out.println(dp[size][groupCnt]); |
| 57 | + } |
| 58 | +} |
| 59 | + |
| 60 | + |
| 61 | +``` |
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