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QOJ
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 |
---|---|---|---|---|---|---|---|---|---|
#225874 | #5458. Shortest Path Query | ZSH_ZSH# | TL | 1ms | 3604kb | C++14 | 2.1kb | 2023-10-25 11:04:06 | 2023-10-25 11:04:07 |
Judging History
answer
#include<bits/stdc++.h>
#define rep(i,a,b) for (register int i=(a);i<=(b);i++)
#define drep(i,a,b) for (register int i=(a);i>=(b);i--)
typedef long long ll;
using namespace std;
vector<array<int,2> > minkowski(vector<array<int,2> > &a,vector<array<int,2> > &b)
{
if (!a.size()) return b;
if (!b.size()) return a;
vector<array<int,2> > c(a.size()+b.size());
{
int i=0,j=0;
while (i<a.size()||j<b.size())
{
if (j==b.size()) c[i+j]=a[i],i++;
else if (i==a.size()) c[i+j]=b[j],j++;
else
{
if (a[i][0]<b[j][0]||(a[i][0]==b[j][0]&&a[i][1]<b[j][1])) c[i+j]=a[i],i++;
else c[i+j]=b[j],j++;
}
}
}
vector<array<int,2> > stk;
for (auto x:c)
{
if (stk.size()&&x[0]==stk.back()[0]&&x[1]>=stk.back()[1]) continue;
while (stk.size()>1)
{
auto a=stk[stk.size()-2],b=stk.back();
array<int,2> u={x[0]-a[0],x[1]-a[1]};
array<int,2> v={b[0]-a[0],b[1]-a[1]};
if (1ll*u[0]*v[1]-1ll*u[1]*v[0]>=0)
{
stk.pop_back();
}
}
stk.push_back(x);
}
return stk;
}
int main()
{
ios::sync_with_stdio(false); cin.tie(0);
int n,m; cin>>n>>m;
vector<vector<array<int,2> > > G(n+1);
rep(i,1,m)
{
int u,v,w; cin>>u>>v>>w;
G[v].push_back({u,w});
}
vector<vector<array<int,2> > > vec(n+1);
vec[1].push_back({0,0});
rep(i,2,n)
{
vector<array<int,2> > now;
for (auto v:G[i])
{
auto t=vec[v[0]];
for (auto &x:t)
{
if (v[1]==0) x[0]++;
else x[1]++;
}
now=minkowski(now,t);
}
vec[i]=now;
}
// rep(i,1,n)
// {
// printf("vec %d : ",i);
// for (auto x:vec[i]) printf("(%d,%d) ",x[0],x[1]);
// printf("\n");
// }
int q; cin>>q;
rep(_,1,q)
{
int a,b,x; cin>>a>>b>>x;
int l=0,r=vec[x].size()-1;
while (r-l>3)
{
int m1=(l+l+r)/3,m2=(l+r+r)/3;
ll v1=1ll*a*vec[x][m1][0]+1ll*b*vec[x][m1][1];
ll v2=1ll*a*vec[x][m2][0]+1ll*b*vec[x][m2][1];
if (v2>=v1) r=m2;
else l=m1;
}
ll ans=1e18;
rep(i,l,r) ans=min(ans,1ll*a*vec[x][i][0]+1ll*b*vec[x][i][1]);
printf("%lld\n",ans);
}
return 0;
}
詳細信息
Test #1:
score: 100
Accepted
time: 1ms
memory: 3604kb
input:
4 4 1 2 0 1 3 1 2 4 0 3 4 1 3 3 5 2 3 2 4 2 3 4
output:
3 4 4
result:
ok 3 number(s): "3 4 4"
Test #2:
score: -100
Time Limit Exceeded
input:
50000 100000 1 2 1 2 3 0 3 4 1 4 5 0 5 6 1 6 7 0 7 8 1 8 9 1 9 10 0 10 11 1 11 12 1 12 13 1 13 14 0 14 15 0 15 16 0 16 17 0 17 18 1 18 19 1 19 20 0 20 21 1 21 22 0 22 23 0 23 24 1 24 25 1 25 26 0 26 27 1 27 28 0 28 29 0 29 30 0 30 31 0 31 32 1 32 33 0 33 34 1 34 35 1 35 36 1 36 37 1 37 38 0 38 39 0 ...