环状数组最大子串和 最大和最小是相对的

#include<iostream>
#include<cstdio>
#include<cstring>
#include<cstdlib>
#include<string>
using namespace std;

void dp() {
   int i,t1,t2;
   t1 = arra[0];
   t2 = arra[0];
   Max = t1;
   Min = t2;
   for( i = 1 ; i < n ; i ++)
   {
      if(t1 <= 0)
         t1 = arra[i];
      else
         t1 += arra[i];
      if(t2 >= 0)
         t2 = arra[i];
      else
         t2 += arra[i];
      Max = max(t1,Max);
      Min = min(t2,Min);
   }
   Max = max(Max,total-Min);
   printf("%d\n",max(Max,0));
}
 
int main() {
   while(~scanf("%d",&n))
   {
      total = 0; 
      for(int i = 0 ; i < n ; i ++)
      {
         scanf("%d",&arra[i]);
         total += arra[i];
      }
      dp(); 
   }
   return 0;
}