为啥我100分却wa了一个点？qwq

#include <bits/stdc++.h>

using namespace std;

typedef long long ll;
const int N=5e4+2;
ll L;
int n,m; 
ll d[N];

bool check(int x){
	int last=0,cnt=0;
	for(int i = 1;i<=n;i++){
		if(d[i]-last>=x) last=d[i];
		else cnt++;
	}
	return cnt<=m;
}

int main(){
	scanf("%lld%d%d",&L,&n,&m);
	for(int i = 1;i<=n;i++)scanf("%lld",&d[i]);
	d[n+1]=L;
	int r=L,l=1;
	while(l<r){
		int mid = (l+r+1)>>1;
		if(check(mid))l=mid;
		else r = mid-1;
	}
	cout << r;
	puts("");
	return 0;
}