#include <bits/stdc++.h>
using namespace std;
#define sf scanf
#define pf printf
#define fi first
#define se second
#define pb push_back
#define sz(x) (int)x.size()
#define all(x) x.begin(),x.end()
#define INF 1023456789
typedef long long ll;
typedef long double ld;
struct frac{
ll a,b;
};
typedef pair<frac,frac> ii;
int n,h,x[1000005],y[1000005];
vector<ii> v;
int main(){
sf("%d%d",&n,&h);
for(int i=1;i<=n;++i)sf("%d%d",&x[i],&y[i]);
for(int i=3;i<n;i+=2){
int x1=x[i-1],x2=x[i],y1=y[i-1],y2=y[i];
frac a={(ll)h*(x2-x1)-y1*x2+x1*y2,y2-y1};
if(a.b<0)a.a=-a.a,a.b=-a.b;
x1=x[i],x2=x[i+1],y1=y[i],y2=y[i+1];
frac b={(ll)h*(x2-x1)-y1*x2+x1*y2,y2-y1};
if(b.b<0)b.a=-b.a,b.b=-b.b;
v.pb({a,b});
}
sort(all(v),[](ii &a,ii &b){return a.se.a*b.se.b<a.se.b*b.se.a;});
int ans=0;frac pv=v[0].fi;
pv.a-=1;
for(int i=0;i<sz(v);++i){
if(pv.a*v[i].fi.b<pv.b*v[i].fi.a){
++ans;
pv=v[i].se;
}
}
pf("%d\n",ans);
}
Compilation message
Main.cpp: In function 'int main()':
Main.cpp:25:4: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
25 | sf("%d%d",&n,&h);
| ^
Main.cpp:26:25: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
26 | for(int i=1;i<=n;++i)sf("%d%d",&x[i],&y[i]);
| ^
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
2 ms |
724 KB |
Output is correct |
| 2 |
Incorrect |
5 ms |
768 KB |
Output isn't correct |
| 3 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
1 ms |
340 KB |
Output is correct |
| 2 |
Incorrect |
1 ms |
340 KB |
Output isn't correct |
| 3 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
2 ms |
724 KB |
Output is correct |
| 2 |
Incorrect |
5 ms |
768 KB |
Output isn't correct |
| 3 |
Halted |
0 ms |
0 KB |
- |
