求助20pts

#include<iostream>
#define ansmax 1000000000
using namespace std;
int a[100010],n,m;
int ans=0;

int check(int a[],int x){
    int v=0,nm=0,in=1;
    while(1){
        v+=a[in];in++;
        if(v>x){
            in--;v=0;nm++;
        }
        if(nm>m) return 0;
        if(in>n) return 1;
    }
}

int find(int L,int R){
    int ans;
    while(L<=R){
        int mid=(L+R)/2;
        if(check(a,mid)){
            ans=mid;R=mid-1;
        }
        else L=mid+1;
    }
    return ans;
}

int main(){
    cin>>n>>m;
    for(int i=1;i<=n;i++) cin>>a[i];
    int ans=find(1,ansmax);
    cout<<ans<<endl;
    return 0;
}