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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 |
---|---|---|---|---|---|---|---|---|---|
#725609 | #5426. Drain the Water Tank | hellocccl | WA | 1ms | 5836kb | C++20 | 1.4kb | 2024-11-08 19:03:48 | 2024-11-08 19:03:48 |
Judging History
answer
//ALL IN
//#pragma GCC optimize("Ofast")
//#pragma GCC optimize("Ofast,no-stack-protector,unroll-loops,fast-math")
//#pragma GCC target("sse,sse2,sse3,ssse3,sse4.1,sse4.2,avx,avx2,popcnt,tune=native")
#include<bits/stdc++.h>
using namespace std;
using ll=long long;
#define int long long
#define double long double
const int N=2e6+7;
const int mod=1e9+7;
const int inf=4e18;
mt19937 rnd(time(0));
clock_t start,over;// start=clock(); last=(final-over)*1.0/1000
inline int read(){int x=0,f=1;char ch=getchar();while(ch<'0'||ch>'9'){if(ch=='-')f=-1;ch=getchar();}while(ch>='0'&&ch<='9'){x=x*10+ch-'0',ch=getchar();}return x*f;}
inline void write(int x){if(x<0)putchar('-'),x=-x;if(x>9)write(x/10);putchar(x%10+'0');return;}
struct node {
int x;
int y;
};
struct node a[N];
int pre[N];
int n,k;
int cross(int x1,int y1,int x2,int y2){
return x1*y2-x2*y1;
}
void solve(){
cin>>n;
for(int i=0;i<n;i++){
cin>>a[i].x>>a[i].y;
}
int pre=0,next=1,ans=0;
for(int i=0;i<n;i++){
while(a[i].y==a[next].y){
next=(next+1)%n;
}
pre=(i-1+n)%n;
if(a[i].y<a[pre].y&&a[i].y<a[next].y){
if(a[i].y==a[(i+1)%n].y){
continue;
}
if(cross(a[i].x-a[pre].x,a[i].y-a[pre].y,a[next].x-a[i].x,a[next].y-a[i].y)>0){
ans++;
}
else if(a[i].x<a[(i+1)%n].x){
ans++;
}
}
}
cout<<ans<<"\n";
}
signed main(){
ios::sync_with_stdio(0),cin.tie(0),cout.tie(0);
int _=1;
//cin>>_;
while(_--)solve();
}
詳細信息
Test #1:
score: 100
Accepted
time: 1ms
memory: 5836kb
input:
6 0 0 1 1 2 1 3 0 3 2 0 2
output:
2
result:
ok 1 number(s): "2"
Test #2:
score: -100
Wrong Answer
time: 1ms
memory: 5724kb
input:
8 4 4 0 4 0 2 1 2 2 2 2 0 3 0 4 0
output:
0
result:
wrong answer 1st numbers differ - expected: '1', found: '0'