poj Monthly Expense

http://poj.org/problem?id=3273

 #include<cstdio>
 #include<cstring>
 #include<cmath>
 #include<algorithm>
 #define maxn 100010
 using namespace std;

 int n,s;
 int a[maxn];

 int main()
 {
     while(scanf("%d%d",&n,&s)!=EOF){
     int high=,low=;
     for(int i=; i<n; i++)
     {
         scanf("%d",&a[i]);
         high+=a[i];
         low=max(low,a[i]);
     }
     int mid;
     while(low<=high)
     {
         mid=(high+low)/;
         int ans=,sum=;
         for(int i=; i<n; i++)
         {
             sum+=a[i];
             if(sum>mid)
             {
                 ans++;
                 sum=a[i];
             }
         }
         if(sum!=) ans++;
         if(ans>s)
         {
             low=mid+;
         }
         else high=mid-;
     }
     printf("%d\n",mid);
     }
     return ;
 }