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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 |
---|---|---|---|---|---|---|---|---|---|
#786704 | #5426. Drain the Water Tank | Awei | WA | 0ms | 3636kb | C++20 | 1.4kb | 2024-11-26 22:58:46 | 2024-11-26 22:58:46 |
Judging History
answer
#include <bits/stdc++.h>
using namespace std;
typedef long long LL;
double cross(double x1, double y1, double x2, double y2){
// cout << x1 << " " << y1 << endl;
// cout << x2 << " " << y2 << endl;
return x1 * y2 - x2 * y1;
}
void solve(){
int n;
cin >> n;
int lid = 1;
vector<pair<int, int>> a(2 * n + 1);
for(int i = 1; i <= n; i++){
cin >> a[i].first >> a[i].second;
if(a[i].second > a[lid].second) lid = i;
else if(a[i].second == a[lid].second && a[i].first < a[lid].first) lid = i;
}
for(int i = 1; i <= n; i++){
a[n + i] = a[i];
}
int ans = 0;
auto [lx, ly] = a[lid];
for(int i = lid + 1; i <= n + lid; i++){
auto [x, y] = a[i];
auto [xx, yy] = a[i + 1];
// cout << i << endl;
// cout << lx << " " << ly << endl;
// cout << x << " " << y << endl;
// cout << xx << " " << yy << endl;
if(y > ly){
lx = x;
ly = y;
}
if(yy > y && cross(x - lx, y - ly, xx - x, yy - y) >= 0){
lx = xx;
ly = yy;
ans++;
}
// cout << ans << endl;
// cout << "-------" << endl;
}
cout << ans << "\n";
return;
}
int main(){
ios::sync_with_stdio(false);
cin.tie(nullptr);
int T = 1;
while(T--){
solve();
}
return 0;
}
详细
Test #1:
score: 100
Accepted
time: 0ms
memory: 3636kb
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: 0
Accepted
time: 0ms
memory: 3612kb
input:
8 4 4 0 4 0 2 1 2 2 2 2 0 3 0 4 0
output:
1
result:
ok 1 number(s): "1"
Test #3:
score: 0
Accepted
time: 0ms
memory: 3484kb
input:
7 1 0 3 4 0 3 1 2 2 3 1 1 0 2
output:
2
result:
ok 1 number(s): "2"
Test #4:
score: -100
Wrong Answer
time: 0ms
memory: 3604kb
input:
6 0 0 2 0 1 1 4 1 5 0 3 4
output:
1
result:
wrong answer 1st numbers differ - expected: '2', found: '1'