oj.uz

답안 #57412

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
57412 2018-07-15T00:48:36 Z red1108 먼 별 (KOI16_dist) C++17
2 / 100
 910 ms 5204 KB 
#include <stdio.h>
#include <algorithm>
using namespace std;
typedef long long ll;
struct star{
    ll xx,yy,dx,dy;
}input[30010];
ll n,maxday,top;
struct nowstar{
    ll x, y;
}now[30010],st[30010];
ll cross(ll a, ll b, ll c, ll d)
{
    return (ll)((ll)a*d-(ll)b*c);
}
bool ccmp(nowstar A, nowstar B)
{
    if(A.x==B.x) return A.y<B.y;
    return A.x<B.x;
}
bool rcmp(nowstar A, nowstar B)
{
    return cross(A.x-now[1].x,A.y-now[1].y,B.x-now[1].x,B.y-now[1].y)>0;
}
ll f(ll x){return abs(((x-1)%top)+1);}
ll dist(nowstar A, nowstar B)
{
    return ((B.x-A.x)*(B.x-A.x)+(B.y-A.y)*(B.y-A.y));
}
ll maxdis(ll day)
{
    ll i,j;
    top=0;
    for(i=1;i<=n;i++)
    {
        now[i].x=input[i].xx+input[i].dx*day;
        now[i].y=input[i].yy+input[i].dy*day;
    }
    sort(now+1,now+n+1,ccmp);
    sort(now+2,now+n+1,rcmp);
    st[++top]=now[1];
    st[++top]=now[2];
    for(i=3;i<=n;i++)
    {
        while(top>=2&&cross(st[top].x-st[top-1].x,st[top].y-st[top-1].y,now[i].x-st[top].x,now[i].y-st[top].y)<=0) top--;
        st[++top]=now[i];
    }
    ll ret=0;
    if(top==1||top==0) return 0;
    if(top==2) return dist(st[1],st[2]);
    for(i=1,j=2;i<=top;i++)
    {
        while(cross(st[f(i+1)].x-st[f(i)].x,st[f(i+1)].y-st[f(i)].y,st[f(j+1)].x-st[f(j)].x,st[f(j+1)].y-st[f(j)].y)>0)j++;
        ret=max(ret,dist(st[f(i)],st[f(j)]));
        ret=max(ret,dist(st[f(i)],st[f(j+1)]));
    }
    return ret;
}
int main()
{
    ll i;
    scanf("%lld %lld",&n, &maxday);
    for(i=1;i<=n;i++)
    {
        scanf("%lld %lld %lld %lld", &input[i].xx, &input[i].yy, &input[i].dx, &input[i].dy);
    }
    ll l=0, r=maxday, x1, x2,ci=50;
    while(ci--&&l+1<r)
    {
        x1=((ll)2*l+r)/3;
        x2=((ll)2*r+l)/3;
        if(maxdis(x1)>maxdis(x2)) l=x1;
        else r=x2;
    }
    ll ans1=maxdis(l),ans2=l;
    for(i=l+1;i<=r;i++)
    {
        if(maxdis(i)<ans1)
        {
            ans1=maxdis(i);
            ans2=i;
        }
    }
    printf("%lld\n%lld", ans2,ans1);
}

Compilation message

dist.cpp: In function 'int main()':
dist.cpp:62:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%lld %lld",&n, &maxday);
     ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
dist.cpp:65:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%lld %lld %lld %lld", &input[i].xx, &input[i].yy, &input[i].dx, &input[i].dy);
         ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Subtask #1
2.0 / 2.0

# 결과 실행 시간 메모리 Grader output
1 Correct 2 ms 248 KB Output is correct
2 Correct 2 ms 360 KB Output is correct
3 Correct 2 ms 528 KB Output is correct
4 Correct 2 ms 528 KB Output is correct
5 Correct 2 ms 604 KB Output is correct
6 Correct 3 ms 604 KB Output is correct
7 Correct 3 ms 604 KB Output is correct
8 Correct 2 ms 604 KB Output is correct
9 Correct 2 ms 604 KB Output is correct
10 Correct 2 ms 612 KB Output is correct

Subtask #2
0 / 40.0

# 결과 실행 시간 메모리 Grader output
1 Correct 2 ms 248 KB Output is correct
2 Correct 2 ms 360 KB Output is correct
3 Correct 2 ms 528 KB Output is correct
4 Correct 2 ms 528 KB Output is correct
5 Correct 2 ms 604 KB Output is correct
6 Correct 3 ms 604 KB Output is correct
7 Correct 3 ms 604 KB Output is correct
8 Correct 2 ms 604 KB Output is correct
9 Correct 2 ms 604 KB Output is correct
10 Correct 2 ms 612 KB Output is correct
11 Correct 22 ms 628 KB Output is correct
12 Correct 25 ms 652 KB Output is correct
13 Correct 15 ms 676 KB Output is correct
14 Correct 22 ms 824 KB Output is correct
15 Incorrect 17 ms 824 KB Output isn't correct
16 Halted 0 ms 0 KB -

Subtask #3
0 / 39.0

# 결과 실행 시간 메모리 Grader output
1 Correct 883 ms 2816 KB Output is correct
2 Correct 910 ms 3340 KB Output is correct
3 Correct 814 ms 4004 KB Output is correct
4 Correct 155 ms 5196 KB Output is correct
5 Incorrect 88 ms 5204 KB Output isn't correct
6 Halted 0 ms 0 KB -

Subtask #4
0 / 19.0

# 결과 실행 시간 메모리 Grader output
1 Correct 2 ms 248 KB Output is correct
2 Correct 2 ms 360 KB Output is correct
3 Correct 2 ms 528 KB Output is correct
4 Correct 2 ms 528 KB Output is correct
5 Correct 2 ms 604 KB Output is correct
6 Correct 3 ms 604 KB Output is correct
7 Correct 3 ms 604 KB Output is correct
8 Correct 2 ms 604 KB Output is correct
9 Correct 2 ms 604 KB Output is correct
10 Correct 2 ms 612 KB Output is correct
11 Correct 22 ms 628 KB Output is correct
12 Correct 25 ms 652 KB Output is correct
13 Correct 15 ms 676 KB Output is correct
14 Correct 22 ms 824 KB Output is correct
15 Incorrect 17 ms 824 KB Output isn't correct
16 Halted 0 ms 0 KB -