結果

問題 No.2438 Double Least Square
コンテスト
ユーザー rikein12
提出日時 2023-08-18 22:47:15
言語 PyPy3
(7.3.15)
結果
WA  
実行時間 -
コード長 2,410 bytes
コンパイル時間 392 ms
コンパイル使用メモリ 82,176 KB
実行使用メモリ 129,764 KB
最終ジャッジ日時 2024-11-28 09:01:35
合計ジャッジ時間 39,794 ms
ジャッジサーバーID
（参考情報） 		judge4 / judge1
このコードへのチャレンジ
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ファイルパターン 結果
sample AC * 2 WA * 1
other AC * 10 WA * 20
権限があれば一括ダウンロードができます

ソースコード

diff # 

import random
N = int(input())
H = int(input())

X = []
for i in range(N):
    x,y = list(map(int,input().split()))
    X.append((x,y))

ans = 10**18

def calc(coef, xp, yp):
    a2 = yp/(xp+1e-9)
    a1 = (yp-H)/(xp+1e-9)
    return coef[0] + a1*coef[1] + (a1*a1)*coef[2] +\
        a2*coef[3] + (a2*a2)*coef[4]

coef1 = [[[0]*3 for j in range(501)] for i in range(501)]
coef2 = [[[0]*3 for j in range(501)] for i in range(501)]

for x,y in X:
    coef1[x][y][0] += ((y - H)**2)
    coef1[x][y][1] += (- 2*x*(y - H))
    coef1[x][y][2] += (x**2)
    coef2[x][y][0] += y**2
    coef2[x][y][1] += - 2*x*y
    coef2[x][y][2] += x**2
for x in range(501):
    for y in range(501):
        for i in range(3):
            if x>=1 and y>=1:
                coef1[x][y][i] += coef1[x-1][y][i] + coef1[x][y-1][i] - coef1[x-1][y-1][i]
                coef2[x][y][i] += coef2[x-1][y][i] + coef2[x][y-1][i] - coef2[x-1][y-1][i]
            elif x==0 and y>=1:
                coef1[x][y][i] += coef1[x][y-1][i]
                coef2[x][y][i] += coef2[x][y-1][i]
            elif y==0 and x>=1:
                coef1[x][y][i] += coef1[x-1][y][i]
                coef2[x][y][i] += coef2[x-1][y][i]


for xp in range(501):
    for yp in range(501):
        coef = [0]*5
        coef[0] += coef2[500][500][0] - coef2[500][yp][0] - coef2[xp][500][0] + 2*coef2[xp][yp][0]
        coef[3] += coef2[500][500][1] - coef2[500][yp][1] - coef2[xp][500][1] + 2*coef2[xp][yp][1]
        coef[4] += coef2[500][500][2] - coef2[500][yp][2] - coef2[xp][500][2] + 2*coef2[xp][yp][2]
        coef[0] += coef1[500][yp][0] + coef1[xp][500][0] - 2*coef1[xp][yp][0]
        coef[1] += coef1[500][yp][1] + coef1[xp][500][1] - 2*coef1[xp][yp][1]
        coef[2] += coef1[500][yp][2] + coef1[xp][500][2] - 2*coef1[xp][yp][2]
        ans = min(calc(coef, xp, yp), ans)
        ans = min(calc(coef, xp, yp+1), ans)
        ans = min(calc(coef, xp+1, yp), ans)
        ans = min(calc(coef, xp+1, yp+1), ans)
        for i in range(50):
            ans = min(calc(coef, xp + random.uniform(0,1), yp + random.uniform(0, 1)), ans)
        if abs(- coef[3]/(2*(coef[4]+1e-9)) + coef[1]/(2*(coef[2]+1e-9))) > 1e-9:
            xtest = H/(- coef[3]/(2*(coef[4]+1e-9)) + coef[1]/(2*(coef[2]+1e-9)))
            ytest = xtest * (- coef[3]/(2*(coef[4]+1e-9)))
            ans = min(calc(coef, min(max(xtest,xp),xp+1), min(max(ytest,yp),yp+1)), ans)


print(ans)
0