poj1089

简单题

View Code

   
     

    
      #include 
    
      <
    
      iostream
    
      >
    
      
#include 
    
      <
    
      cstdio
    
      >
    
      
#include 
    
      <
    
      cstdlib
    
      >
    
      
#include 
    
      <
    
      cstring
    
      >
    
      
#include 
    
      <
    
      algorithm
    
      >
    
      

    
      using
    
       
    
      namespace
    
       std;


    
      #define
    
       maxn 50005
    
      


    
      struct
    
       Interval
{
 
    
      int
    
       a, b;
}interval[maxn];


    
      int
    
       n;


    
      bool
    
       
    
      operator
    
       
    
      <
    
       (
    
      const
    
       Interval 
    
      &
    
      a, 
    
      const
    
       Interval 
    
      &
    
      b)
{
 
    
      if
    
       (a.a 
    
      ==
    
       b.a)
 
    
      return
    
       a.b 
    
      <
    
       b.b;
 
    
      return
    
       a.a 
    
      <
    
       b.a;
}


    
      int
    
       main()
{
 
    
      //
    
      freopen("t.txt", "r", stdin);
    
      

    
       scanf(
    
      "
    
      %d
    
      "
    
      , 
    
      &
    
      n);
 
    
      for
    
       (
    
      int
    
       i 
    
      =
    
       
    
      0
    
      ; i 
    
      <
    
       n; i
    
      ++
    
      )
 scanf(
    
      "
    
      %d%d
    
      "
    
      , 
    
      &
    
      interval[i].a, 
    
      &
    
      interval[i].b);
 sort(interval, interval 
    
      +
    
       n);
 
    
      int
    
       s 
    
      =
    
       interval[
    
      0
    
      ].a;
 
    
      int
    
       e 
    
      =
    
       interval[
    
      0
    
      ].b;
 
    
      for
    
       (
    
      int
    
       i 
    
      =
    
       
    
      1
    
      ; i 
    
      <
    
       n; i
    
      ++
    
      )
 {
 
    
      if
    
       (interval[i].a 
    
      <=
    
       e)
 e 
    
      =
    
       max(interval[i].b, e);
 
    
      else
    
      
 {
 printf(
    
      "
    
      %d %d\n
    
      "
    
      , s, e);
 s 
    
      =
    
       interval[i].a;
 e 
    
      =
    
       interval[i].b;
 }
 }
 printf(
    
      "
    
      %d %d\n
    
      "
    
      , s, e);
 
    
      return
    
       
    
      0
    
      ;
}