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ID题目提交者结果用时内存语言文件大小提交时间测评时间
#186969#3857. Single-track railwaySuiseiseki#WA 0ms1656kbC++14956b2023-09-24 13:36:112023-09-24 13:36:12

Judging History

你现在查看的是最新测评结果

  • [2023-09-24 13:36:12]
  • 评测
  • 测评结果:WA
  • 用时:0ms
  • 内存:1656kb
  • [2023-09-24 13:36:11]
  • 提交

answer

#include <cstdio>
#include <algorithm>
typedef long long ll;
const int Maxn=200000;
int n,k;
int a[Maxn+5];
ll f[Maxn+5],sum;
void add(int x,int v){
	v=v-a[x];
	sum+=v;
	a[x]=v;
	for(int i=x;i<=n;i+=(i&(-i))){
		f[i]+=v;
	}
}
ll query(int x){
	ll ans=0;
	for(int i=x;i>0;i-=(i&(-i))){
		ans+=f[i];
	}
	return ans;
}
int log_2(int x){
	return 31-__builtin_clz(x);
}
int find_mid(ll v){
	ll val=0;
	int ans=0;
	for(int i=log_2(n);i>=0;i--){
		if(((ans|(1<<i))<=n)&&val+f[ans|(1<<i)]<=v){
			ans|=(1<<i);
			val+=f[ans];
		}
	}
	return ans;
}
void print_ans(){
	int pos=find_mid(sum/2);
	ll ans=std::min(2*query(pos+1)-sum,sum-2*query(pos));
	printf("%lld\n",ans);
}
int main(){
	scanf("%d",&n);
	n--;
	for(int i=1;i<=n;i++){
		int v;
		scanf("%d",&v);
		add(i,v);
	}
	print_ans();
	scanf("%d",&k);
	for(int i=1;i<=k;i++){
		int x,v;
		scanf("%d%d",&x,&v);
		add(x,v);
		print_ans();
	}
	return 0;
}

詳細信息

Test #1:

score: 0
Wrong Answer
time: 0ms
memory: 1656kb

input:

2
39
7
1 20
1 70
1 56
1 37
1 37
1 37
1 91

output:

39
20
109
76
146
113
183
204

result:

wrong answer 3rd lines differ - expected: '70', found: '109'