poj2593

Max Sequence

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|code--------------------------------------------------------------------------------------------------+ |001| /***************************************************************\                               |002|  *Author: 小呼                                                                                |003|  *Created Time: Tue 06 Jul 2010 02:49:20 PM CST                                                 |004|  *File Name: a.cpp                                                                              |005|  *Description:动态规划。Max_L[i]表示A[1...i]中最大的连续和，同理               |006|  *Max_R[i]是指A[i...n]中最大的连续和                                                   |007| \***************************************************************/                               |008| //*======================*Head File*======================*\\                                   |009|                                                                                                 |010| #include<iostream>                                                                              |011| #include<stdio.h>                                                                               |012| #include<stdlib.h>                                                                              |013| #include<string.h>                                                                              |014| /*----------------------*Global Variable*----------------------*/                               |015|                                                                                                 |016| //*=====================*Main Program*=====================*//                                  |017| using namespace std;                                                                            |018| int A[100001],n,Max_L[100001],Max_R[100001];                                                    |019| int main(){                                                                                     |020| .       while(scanf("%d",&n)!=EOF&&n){                                                          |021| .       .       for(int i=1;i<=n;++i)                                                           |022| .       .         scanf("%d",A+i);                                                              |023| .       .       int _max=-9999999,temp=-9999999;                                                |024| .       .       for(int i=1;i<n;++i){                                                           |025| .       .       .       if(temp>=0)                                                             |026| .       .       .         temp+=A[i];                                                           |027| .       .       .       else                                                                    |028| .       .       .       .       temp=A[i];                                                      |029| .       .       .       _max=_max>temp?_max:temp;                                               |030| .       .       .       Max_L[i]=_max;                                                          |031| .       .       }                                                                               |032| .       .       _max=temp=-999999;                                                              |033| .       .       for(int i=n;i>1;--i){                                                           |034| .       .       .       if(temp>0)                                                              |035| .       .       .         temp+=A[i];                                                           |036| .       .       .       else                                                                    |037| .       .       .         temp=A[i];                                                            |038| .       .       .       _max=_max>temp?_max:temp;                                               |039| .       .       .       Max_R[i]=_max;                                                          |040| .       .       }                                                                               |041| .       .       int res=-999999;                                                                |042| .       .       for(int i=1;i<n;++i){                                                           |043| .       .       .       res=(res>Max_L[i]+Max_R[i+1]?res:Max_L[i]+Max_R[i+1]);                  |044| .       .       }                                                                               |045| .       .       printf("%d\n",res);                                                             |046| .       }                                                                                       |047| .       return 0;                                                                               |048| }                                                                                               end+--------------------------------------------------------------------------------------------------+