Poj Solution 1201

http://poj.org/problem?id=1201

//* @author: ccQ.SuperSupper
import java.io.*;
import java.util.*;
class Intervals{
    int left,right,ci;
}
public class Main {
 static final int N = 50000+10;
 static int DP[] = new int[N],n,left,right;
 static Intervals Inter[] = new Intervals[N];
    
 static void start(){
    for(int i=0;i< N;++i)
        Inter[i] = new Intervals();
 }
 static int Get_Num(StreamTokenizer cin) throws Exception{
    if(cin.nextToken()==StreamTokenizer.TT_EOF)
        return -1;
    return (int) cin.nval;
 }

 static int solve(){
  int i,j;
  boolean flag=true;
  for(i=left;i<=right;++i)
     DP[i] = -N;
  DP[left] = 0;
  for(i=left;i<=right && flag;++i){
    flag = false;
   for(j=0;j< n;++j)if(DP[Inter[j].left]>-N && DP[Inter[j].left]+Inter[j].ci>DP[Inter[j].right]){
        DP[Inter[j].right]= DP[Inter[j].left]+Inter[j].ci ;
        flag = true;
    }
   for(j=left;j< right;++j) if(DP[j]>-N && DP[j]>DP[j+1]){
    DP[j+1] = DP[j];
    flag = true;
   }
   for(j=right;j>left;--j) if(DP[j]>-N && DP[j]-1>DP[j-1]){
    DP[j-1] = DP[j]-1;
    flag = true;
   }
  }
    return DP[right];
 }

 public static void main(String[]args) throws Exception{
  int i,j;
  start();
  StreamTokenizer cin =new StreamTokenizer(new BufferedReader(new InputStreamReader(System.in)));
        
  while((n = Get_Num(cin))>0){
    left = N ; right = 0;
    for(i=0;i< n;++i){
          Inter[i].left = Get_Num(cin);
      Inter[i].right = Get_Num(cin)+1;
      Inter[i].ci = Get_Num(cin);
      left = Min(left,Inter[i].left);
      right = Max(right,Inter[i].right);
    }
    System.out.println(solve());
   }
        
 }

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

  static int Min(int a,int b){
    return a< b?a:b;
  }
}