AGC008 A - Simple Calculator
備忘録
問題
回答
import sys import os import math import bisect import itertools import collections import heapq import queue import array import time # 時々使う # import numpy as np # from decimal import Decimal, ROUND_HALF_UP # from scipy.sparse.csgraph import csgraph_from_dense, floyd_warshall # from collections import defaultdict, deque # 再帰の制限設定 sys.setrecursionlimit(10000000) def ii(): return int(sys.stdin.buffer.readline().rstrip()) def il(): return list(map(int, sys.stdin.buffer.readline().split())) def fl(): return list(map(float, sys.stdin.buffer.readline().split())) def iln(n): return [int(sys.stdin.buffer.readline().rstrip()) for _ in range(n)] def iss(): return sys.stdin.buffer.readline().decode().rstrip() def sl(): return list(map(str, sys.stdin.buffer.readline().decode().split())) def isn(n): return [sys.stdin.buffer.readline().decode().rstrip() for _ in range(n)] def lcm(x, y): return (x * y) // math.gcd(x, y) # MOD = 10 ** 9 + 7 MOD = 998244353 INF = float('inf') def main(): if os.getenv("LOCAL"): sys.stdin = open("input.txt", "r") x, y = il() if x == y: print(0) exit() if x > 0 and y > 0: if x > y: print(abs(x-y)+2) else: print(abs(x-y)) elif x < 0 and y < 0: if x > y: print(abs(x-y)+2) else: print(abs(x-y)) elif x > 0 and y < 0: y *= -1 print(abs(x-y)+1) elif x < 0 and y > 0: x *= -1 print(abs(x-y)+1) elif x < 0 and y == 0: print(abs(x)) elif x > 0 and y == 0: print(x + 1) elif x == 0 and y < 0: y *= -1 print(abs(x-y)+1) elif x == 0 and y > 0: print(y) if __name__ == '__main__': main()
考え方
上記の回答例は、取りうるパターンをとりあえず全て書いて通した愚直実装。
しかしながら、押すボタンのパターンはA, BA, AB, BAB
の4パターンだけなので、
これらについて網羅する下記のような回答がバグも起き辛く良い。
def main(): if os.getenv("LOCAL"): sys.stdin = open("input.txt", "r") x, y = il() ret = 10**10 if x <= y: # A ret = min(ret, y-x) if -x <= y: # BA ret = min(ret, y+x+1) if y <= x: # BAB ret = min(ret, x-y+2) if -y >= x: # AB ret = min(ret, -y-x+1) print(ret)