Submission #333135

#TimeUsernameProblemLanguageResultExecution timeMemory
333135KWang31Split the sequence (APIO14_sequence)Java
Compilation error
0 ms0 KiB
//By Spontaneous Combustion, just used for test import java.io.*; import java.util.*; public class Main { public static void main(final String[] args) throws IOException { final int N = readInt(); final int K = readInt(); final long[] sum = new long[N + 1]; for (int i = 1; i <= N; i++) { sum[i] = sum[i - 1] + readInt(); } final LineContainer lines = new LineContainer(N); final long[][] dp = new long[2][N]; for (int i = 1; i < N; i++) { dp[1][i] = sum[i] * (sum[N] - sum[i]); } final int[][] prevSplit = new int[K][N]; for (int i = 1, curr = 0, prev = 1; i < K; i++, curr ^= 1, prev ^= 1) { lines.clear(); for (int j = i + 1; j < N; j++) { lines.addLine(j - 1, sum[j - 1], -sum[j - 1] * sum[N] + dp[prev][j - 1]); dp[curr][j] = sum[j] * sum[N] - sum[j] * sum[j] + lines.maxValue(sum[j]); prevSplit[i][j] = lines.getCurrentIndex(); } } long maxPoints = Long.MIN_VALUE; int idx = -1; int curr = K & 1; for (int i = K; i < N; i++) { if (dp[curr][i] > maxPoints) { maxPoints = dp[curr][i]; idx = i; } } System.out.println(maxPoints); for (int i = idx, splitsLeft = K; splitsLeft > 0; splitsLeft--, i = prevSplit[splitsLeft][i]) { System.out.print(i + " "); } System.out.println(); } private static final class LineContainer { private final long[] slopes; private final long[] yInts; private final int[] indexes; private int lines = 0; private int idx = 0; public LineContainer(final int capacity) { this.slopes = new long[capacity]; this.yInts = new long[capacity]; this.indexes = new int[capacity]; } public void addLine(final int index, final long slope, final long yInt) { if (lines > 0 && slopes[lines - 1] == slope && yInts[lines - 1] == yInt) { return; } while (lines >= 2 && intersectionX(slopes[lines - 2], yInts[lines - 2], slope, yInt) < intersectionX(slopes[lines - 2], yInts[lines - 2], slopes[lines - 1], yInts[lines - 1])) { --lines; } indexes[lines] = index; slopes[lines] = slope; yInts[lines++] = yInt; } public long maxValue(final long x) { while (idx + 1 < lines && slopes[idx + 1] * x + yInts[idx + 1] >= slopes[idx] * x + yInts[idx]) { ++idx; } return slopes[idx] * x + yInts[idx]; } public int getCurrentIndex() { return indexes[idx]; } public void clear() { idx = lines = 0; } private static long intersectionX(final long slope1, final long yInt1, final long slope2, final long yInt2) { return (yInt2 - yInt1) / (slope1 - slope2); } } private static final int BUFFER_SIZE = 1 << 16; private static final InputStream in = System.in; private static final byte[] buffer = new byte[BUFFER_SIZE]; private static int bufferPointer = 0, bytesRead = 0; public static String read() throws IOException { final StringBuilder sb = new StringBuilder(); byte c = Read(); while (c <= ' ') { c = Read(); } do { sb.append((char) c); c = Read(); } while (c != -1 && c != ' ' && c != '\n' && c != '\r'); return sb.toString(); } public static String read(final int length) throws IOException { final byte[] ret = new byte[length]; int idx = 0; byte c = Read(); while (c <= ' ') { c = Read(); } do { ret[idx++] = c; c = Read(); } while (c != -1 && c != ' ' && c != '\n' && c != '\r'); return new String(ret, 0, idx); } public static String[] readStringArray(final int strings) throws IOException { final String[] arr = new String[strings]; for (int i = 0; i < strings; i++) { arr[i] = read(); } return arr; } public static String readLine() throws IOException { final StringBuilder sb = new StringBuilder(); byte c = Read(); while (c == '\n' || c == '\r') { c = Read(); } do { sb.append((char) c); c = Read(); } while (c != -1 && c != '\n' && c != '\r'); return sb.toString(); } public static char readChar() throws IOException { byte c = Read(); while (Character.isWhitespace(c)) { c = Read(); } return (char) c; } private static char[] readCharArray(final int chars) throws IOException { final char[] arr = new char[chars]; for (int i = 0; i < chars; i++) { arr[i] = readChar(); } return arr; } public static java.math.BigInteger readBigInteger() throws IOException { return new java.math.BigInteger(read()); } public static java.math.BigDecimal readBigDecimal() throws IOException { return new java.math.BigDecimal(read()); } public static byte readByte() throws IOException { byte ret = 0; byte c = Read(); while (c <= ' ') c = Read(); boolean neg = (c == '-'); if (neg) c = Read(); do { ret = (byte) (ret * 10 + c - '0'); } while ((c = Read()) >= '0' && c <= '9'); if (neg) return (byte) -ret; return ret; } public static byte[] readByteArray(final int numbers) throws IOException { final byte[] arr = new byte[numbers]; for (int i = 0; i < numbers; i++) { arr[i] = readByte(); } return arr; } public static short readShort() throws IOException { short ret = 0; byte c = Read(); while (c <= ' ') c = Read(); boolean neg = (c == '-'); if (neg) c = Read(); do { ret = (short) (ret * 10 + c - '0'); } while ((c = Read()) >= '0' && c <= '9'); if (neg) return (short) -ret; return ret; } public static short[] readShortArray(final int numbers) throws IOException { final short[] arr = new short[numbers]; for (int i = 0; i < numbers; i++) { arr[i] = readShort(); } return arr; } public static int readInt() throws IOException { int ret = 0; byte c = Read(); while (c <= ' ') c = Read(); boolean neg = (c == '-'); if (neg) c = Read(); do { ret = ret * 10 + c - '0'; } while ((c = Read()) >= '0' && c <= '9'); if (neg) return -ret; return ret; } public static int[] readIntArray(final int numbers) throws IOException { final int[] arr = new int[numbers]; for (int i = 0; i < numbers; i++) { arr[i] = readInt(); } return arr; } public static long readLong() throws IOException { long ret = 0; byte c = Read(); while (c <= ' ') c = Read(); boolean neg = (c == '-'); if (neg) c = Read(); do { ret = ret * 10 + c - '0'; } while ((c = Read()) >= '0' && c <= '9'); if (neg) return -ret; return ret; } public static long[] readLongArray(final int numbers) throws IOException { final long[] arr = new long[numbers]; for (int i = 0; i < numbers; i++) { arr[i] = readLong(); } return arr; } public static double readDouble() throws IOException { double ret = 0, div = 1; byte c = Read(); while (c <= ' ') c = Read(); boolean neg = (c == '-'); if (neg) c = Read(); do { ret = ret * 10 + c - '0'; } while ((c = Read()) >= '0' && c <= '9'); if (c == '.') { while ((c = Read()) >= '0' && c <= '9') { ret += (c - '0') / (div *= 10); } } if (neg) return -ret; return ret; } public static double[] readDoubleArray(final int numbers) throws IOException { final double[] arr = new double[numbers]; for (int i = 0; i < numbers; i++) { arr[i] = readDouble(); } return arr; } private static void fillBuffer() throws IOException { bytesRead = in.read(buffer, bufferPointer = 0, BUFFER_SIZE); if (bytesRead == -1) buffer[0] = -1; } private static byte Read() throws IOException { if (bufferPointer == bytesRead) fillBuffer(); return buffer[bufferPointer++]; } }

Compilation message (stderr)

sequence.java:5: error: class Main is public, should be declared in a file named Main.java
public class Main {
       ^
1 error