Cool J has recently become a businessman Mr. Jackson, and he has to make a lot of phone calls now. Today he has n calls planned. For each call we know the moment ti (in seconds since the start of the day) when it is scheduled to start and its duration di (in seconds). All ti are different. Mr. Jackson is a very important person, so he never dials anybody himself, all calls will be incoming.

Mr. Jackson isn't Caesar and he can't do several things at once. If somebody calls him while he hasn't finished the previous conversation, Mr. Jackson puts the new call on hold in the queue. In this case immediately after the end of the current call Mr. Jackson takes the earliest incoming call from the queue and starts the conversation. If Mr. Jackson started the call at the second t, and the call continues for d seconds, then Mr. Jackson is busy at seconds t, t + 1, ..., t + d - 1, and he can start a new call at second t + d. Note that if Mr. Jackson is not busy talking when somebody calls, he can't put this call on hold.

Mr. Jackson isn't Napoleon either, he likes to sleep. So sometimes he allows himself the luxury of ignoring a call, as if it never was scheduled. He can ignore at most k calls. Note that a call which comes while he is busy talking can be ignored as well.

What is the maximum number of seconds Mr. Jackson can sleep today, assuming that he can choose an arbitrary continuous time segment from the current day (that is, with seconds from the 1-st to the 86400-th, inclusive) when he is not busy talking?

Note that some calls can be continued or postponed to the next day or even later. However, the interval for sleep should be completely within the current day.

Input

The first input line contains a pair of integers n, k (0 ≤ k ≤ n ≤ 4000) separated by a space. Following n lines contain the description of calls for today. The description of each call is located on the single line and consists of two space-separated integers ti and di, (1 ≤ ti, di ≤ 86400). All ti are distinct, the calls are given in the order of strict increasing ti.

Scheduled times of calls [ti, ti + di - 1] can arbitrarily intersect.

Output

Print a number from 0 to 86400, inclusive — the maximally possible number of seconds for Mr. Jackson to sleep today.

Examples

Input

3 2
30000 15000
40000 15000
50000 15000


Output

49999


Input

5 1
1 20000
10000 10000
20000 20000
25000 10000
80000 60000


Output

39999

Note

In the first sample the most convenient way is to ignore the first two calls.

In the second sample it is best to ignore the third call. In this case Mr. Jackson will have been speaking:

  * first call: from 1-st to 20000-th second, 
  * second call: from 20001-st to 30000-th second, 
  * fourth call: from 30001-st to 40000-th second (the third call is ignored), 
  * fifth call: from 80000-th to 139999-th second. 



Thus, the longest period of free time is from the 40001-th to the 79999-th second.
import static java.lang.Math.*;
import java.util.*;
import java.io.*;

public class E {

    public void solve() throws Exception {
        
        int n = nextInt(), k = nextInt();
        int[][] dp = new int[n+1][n+1];
        int[] starts = new int[n+1];
        starts[n] = 86401;
        for (int i=1; i<=n; ++i) {
            int start = nextInt(), d = nextInt();
            starts[i-1] = start;
            dp[i][0] = max(dp[i-1][0],start-1) + d;
            for (int j=1; j<i; ++j)
                dp[i][j] = min(dp[i-1][j-1], max(dp[i-1][j],start-1)+d);
        }
        int res = 0;
        for (int i=0; i<=n; ++i) res = max(res, starts[i]-dp[i][k]-1);
        println(res);
        
    }

    

    ////////////////////////////////////////////////////////////////////////////
    
    boolean showDebug = true;
    static boolean useFiles = false;
    static String inFile = "input.txt";
    static String outFile = "output.txt";

    double EPS = 1e-7;
    int INF = Integer.MAX_VALUE;
    long INFL = Long.MAX_VALUE;
    double INFD = Double.MAX_VALUE;

    
    int absPos(int num) {
        return num<0 ? 0:num;
    }
    long absPos(long num) {
        return num<0 ? 0:num;
    }
    double absPos(double num) {
        return num<0 ? 0:num;
    }
    
    int min(int... nums) {
        int r = Integer.MAX_VALUE;
        for (int i: nums)
            if (i<r) r=i;
        return r;
    }
    int max(int... nums) {
        int r = Integer.MIN_VALUE;
        for (int i: nums)
            if (i>r) r=i;
        return r;
    }
    long minL(long... nums) {
        long r = Long.MAX_VALUE;
        for (long i: nums)
            if (i<r) r=i;
        return r;
    }
    long maxL(long... nums) {
        long r = Long.MIN_VALUE;
        for (long i: nums)
            if (i>r) r=i;
        return r;
    }
    double minD(double... nums) {
        double r = Double.MAX_VALUE;
        for (double i: nums)
            if (i<r) r=i;
        return r;
    }
    double maxD(double... nums) {
        double r = Double.MIN_VALUE;
        for (double i: nums)
            if (i>r) r=i;
        return r;
    }
    
    long sumArr(int[] arr) {
        long res = 0;
        for (int i: arr)
            res+=i;
        return res;
    }
    long sumArr(long[] arr) {
        long res = 0;
        for (long i: arr)
            res+=i;
        return res;
    }
    double sumArr(double[] arr) {
        double res = 0;
        for (double i: arr)
            res+=i;
        return res;
    }

    long partsFitCnt(long partSize, long wholeSize) {
        return (partSize+wholeSize-1)/partSize;
    }

    boolean odd(long num) {
        return (num&1)==1;
    }
    
    boolean hasBit(int num, int pos) {
        return (num&(1<<pos))>0;
    }

    long binpow(long a, int n) {
        long r = 1;
        while (n>0) {
            if ((n&1)!=0) r*=a;
            a*=a;
            n>>=1;
        }
        return r;
    }

    boolean isLetter(char c) {
        return (c>='a' && c<='z') || (c>='A' && c<='Z');
    }
    boolean isLowercase(char c) {
        return (c>='a' && c<='z');
    }
    boolean isUppercase(char c) {
        return (c>='A' && c<='Z');
    }
    boolean isDigit(char c) {
        return (c>='0' && c<='9');
    }
    
    boolean charIn(String chars, String s) {
        if (s==null) return false;
        if (chars==null || chars.equals("")) return true;
        for (int i=0; i<s.length(); ++i)
            for (int j=0; j<chars.length(); ++j)
                if (chars.charAt(j)==s.charAt(i)) return true;
        return false;
    }
    
    String stringn(String s, int n) {
        if (n<1 || s==null) return "";
        StringBuilder sb = new StringBuilder(s.length()*n);
        for (int i=0; i<n; ++i) sb.append(s);
        return sb.toString();
    }
    String str(Object o) {
        if (o==null) return "";
        return o.toString();
    }


    long timer = System.currentTimeMillis();
    void startTimer() {
        timer = System.currentTimeMillis();
    }
    void stopTimer() {
        System.err.println("time: "+(System.currentTimeMillis()-timer)/1000.0);
    }


    static class InputReader {
        private byte[] buf;
        private int bufPos = 0, bufLim = -1;
        private InputStream stream;
        public InputReader(InputStream stream, int size) {
            buf = new byte[size];
            this.stream = stream;
        }
        private void fillBuf() throws IOException {
            bufLim = stream.read(buf);
            bufPos = 0;
        }
        char read() throws IOException {
            if (bufPos>=bufLim) fillBuf(); 
            return (char)buf[bufPos++];
        }
        boolean hasInput() throws IOException {
            if (bufPos>=bufLim) fillBuf();
            return bufPos<bufLim;
        }
    }
    
    static InputReader inputReader;
    static BufferedWriter outputWriter;

    char nextChar() throws IOException {
        return inputReader.read();
    }
    char nextNonWhitespaceChar() throws IOException {
        char c = inputReader.read();
        while (c<=' ') c=inputReader.read();
        return c;
    }
    String nextWord() throws IOException {
        StringBuilder sb = new StringBuilder();
        char c = inputReader.read();
        while (c<=' ') c=inputReader.read();
        while (c>' ') {
            sb.append(c);
            c = inputReader.read();
        }
        return new String(sb);
    }
    String nextLine() throws IOException {
        StringBuilder sb = new StringBuilder();
        char c = inputReader.read();
        while (c<=' ') c=inputReader.read();
        while (c!='\n' && c!='\r') {
            sb.append(c);
            c = inputReader.read();
        }
        return new String(sb);
    }
    int nextInt() throws IOException {
        int r = 0;
        char c = nextNonWhitespaceChar();
        boolean neg = false;
        if (c=='-') neg=true;
        else r=c-48;
        c = nextChar();
        while (c>='0' && c<='9') {
            r*=10;
            r+=c-48;
            c=nextChar();
        }
        return neg ? -r:r;
    }
    long nextLong() throws IOException {
        long r = 0;
        char c = nextNonWhitespaceChar();
        boolean neg = false;
        if (c=='-') neg=true;
        else r = c-48;
        c = nextChar();
        while (c>='0' && c<='9') {
            r*=10L;
            r+=c-48L;
            c=nextChar();
        }
        return neg ? -r:r;
    }
    double nextDouble() throws NumberFormatException, IOException {
        return Double.parseDouble(nextWord());
    }
    int[] nextArr(int size) throws NumberFormatException, IOException {
        int[] arr = new int[size];
        for (int i=0; i<size; ++i)
            arr[i] = nextInt();
        return arr;
    }
    long[] nextArrL(int size) throws NumberFormatException, IOException {
        long[] arr = new long[size];
        for (int i=0; i<size; ++i)
            arr[i] = nextLong();
        return arr;
    }
    double[] nextArrD(int size) throws NumberFormatException, IOException {
        double[] arr = new double[size];
        for (int i=0; i<size; ++i)
            arr[i] = nextDouble();
        return arr;
    }
    String[] nextArrS(int size) throws NumberFormatException, IOException {
        String[] arr = new String[size];
        for (int i=0; i<size; ++i)
            arr[i] = nextWord();
        return arr;
    }
    char[] nextArrCh(int size) throws IOException {
        char[] arr = new char[size];
        for (int i=0; i<size; ++i)
            arr[i] = nextNonWhitespaceChar();
        return arr;
    }
    char[][] nextArrCh(int rows, int columns) throws IOException {
        char[][] arr = new char[rows][columns];
        for (int i=0; i<rows; ++i)
            for (int j=0; j<columns; ++j)
                arr[i][j] = nextNonWhitespaceChar();
        return arr;
    }
    char[][] nextArrChBorders(int rows, int columns, char border) throws IOException {
        char[][] arr = new char[rows+2][columns+2];
        for (int i=1; i<=rows; ++i)
            for (int j=1; j<=columns; ++j)
                arr[i][j] = nextNonWhitespaceChar();
        for (int i=0; i<columns+2; ++i) {
            arr[0][i] = border;
            arr[rows+1][i] = border;
        }
        for (int i=0; i<rows+2; ++i) {
            arr[i][0] = border;
            arr[i][columns+1] = border;
        }
        return arr;
    }

    void printf(String format, Object... args) throws IOException {
        outputWriter.write(String.format(format, args));
    }
    void print(Object o) throws IOException {
        outputWriter.write(o.toString());
    }
    void println(Object o) throws IOException {
        outputWriter.write(o.toString());
        outputWriter.newLine();
    }
    void print(Object... o) throws IOException {
        for (int i=0; i<o.length; ++i) {
            if (i!=0) outputWriter.write(' ');
            outputWriter.write(o[i].toString());
        }
    }
    void println(Object... o) throws IOException {
        print(o);
        outputWriter.newLine();
    }
    void printn(Object o, int n) throws IOException {
        String s = o.toString();
        for (int i=0; i<n; ++i) {
            outputWriter.write(s);
            if (i!=n-1) outputWriter.write(' ');
        }
    }
    void printnln(Object o, int n) throws IOException {
        printn(o, n);
        outputWriter.newLine();
    }
    void printArr(int[] arr) throws IOException {
        for (int i=0; i<arr.length; ++i) {
            if (i!=0) outputWriter.write(' ');
            outputWriter.write(Integer.toString(arr[i]));
        }
    }
    void printArr(long[] arr) throws IOException {
        for (int i=0; i<arr.length; ++i) {
            if (i!=0) outputWriter.write(' ');
            outputWriter.write(Long.toString(arr[i]));
        }
    }
    void printArr(double[] arr) throws IOException {
        for (int i=0; i<arr.length; ++i) {
            if (i!=0) outputWriter.write(' ');
            outputWriter.write(Double.toString(arr[i]));
        }
    }
    void printArr(String[] arr) throws IOException {
        for (int i=0; i<arr.length; ++i) {
            if (i!=0) outputWriter.write(' ');
            outputWriter.write(arr[i]);
        }
    }
    void printArr(char[] arr) throws IOException {
        for (char c: arr) outputWriter.write(c);
    }
    void printlnArr(int[] arr) throws IOException {
        printArr(arr);
        outputWriter.newLine();
    }
    void printlnArr(long[] arr) throws IOException {
        printArr(arr);
        outputWriter.newLine();
    }
    void printlnArr(double[] arr) throws IOException {
        printArr(arr);
        outputWriter.newLine();
    }
    void printlnArr(String[] arr) throws IOException {
        printArr(arr);
        outputWriter.newLine();
    }
    void printlnArr(char[] arr) throws IOException {
        printArr(arr);
        outputWriter.newLine();
    }
    void halt(Object... o) throws IOException {
        if (o.length!=0) println(o);
        outputWriter.flush(); outputWriter.close();
        System.exit(0);
    }
    
    void debug(Object... o) {
        if (showDebug) System.err.println(Arrays.deepToString(o));
    }


    public static void main(String[] args) throws Exception {
        Locale.setDefault(Locale.US);
        if (!useFiles) {
            inputReader = new InputReader(System.in, 1<<16);
            outputWriter = new BufferedWriter(new OutputStreamWriter(System.out), 1<<16);
        } else {
            inputReader = new InputReader(new FileInputStream(new File(inFile)), 1<<16);
            outputWriter = new BufferedWriter(new OutputStreamWriter(new FileOutputStream(new File(outFile))), 1<<16);
        }
        new E().solve();
        outputWriter.flush(); outputWriter.close();
    }
}
