Python算法学习: 竞码编程-蓝桥杯校内选拔赛(初赛)重现赛

oj网站地址:竞码编程-蓝桥杯校内选拔赛(初赛)重现赛

试题A：第N个素数

def isPrime(n):
    if n == 2:
        return True
    for i in range(2, n):
        if n % i == 0:
            return False
    return True


count = 0
for i in range(2, 10000):
    if isPrime(i):
        count += 1
    if count == 300:
        print(i)
        print(count)
        break

试题B：coffee的签到题

如果n是偶数，则无法全部进行染色，如果是奇数，则可以全部进行染色

n = int(input())

if n % 2 == 0:
	print("no")
else:
    print("yes")

试题C：不一样的日期

YY,MM,DD,dd = map(int,input().split())
if dd > 0:
    for i in range(1,dd+1):
        DD += 1
        if DD > 13:
            MM += 1
            DD = 1
        if MM > 23:
            YY += 1
            MM = 1
else:
    for i in range(1,abs(dd)+1):
        DD -= 1
        if DD <= 0:
            MM -= 1
            DD = 13
        if MM <= 0:
            YY -= 1
            MM = 23
print(YY,MM,DD)

试题D：三位分节法

str = input()
str = str[::-1] # 字符串翻转
ans = ""
cnt = 0
for i in range(len(str)):
    if cnt == 3:
        ans = ans + ","
        cnt = 0
    cnt += 1
    ans = ans + str[i]
ans = ans[::-1]
print(ans)

试题E：水坑题

a,b = map(int, input().split())
ans = (a*b) % (pow(10,9)+7)
print(ans)

试题F：站队

Python部分数据超时

n = int(input())
data = []
for i in range(1, n+1):
    tmp = list(map(int, input().split()))
    tmp.append(i)
    data.append(tmp)

data = sorted(data,key=lambda x:x[1])
data = sorted(data,key=lambda x:x[0])

for i in range(n-1):
    print(data[i][2], end=" ")
print(data[n-1][2])

试题G：冷门进制

试题H：拯救阿拉德大陆

n = int(input())
nums = list(map(int, input().split()))
ans = 0

for i in range(1,n+1):
    for num in nums:
        if i % num == 0:
            ans += 1
            break
        else:
            continue
print(ans)

试题J：馋嘴羊

import sys
sys.setrecursionlimit(1000000) # 限制递归深度为

def dfs(x, y):
    if x < 0 or y < 0 or x > n - 1 or y > m - 1 or vis[x][y] == 1 or arr[x][y] == '0':
        return
    vis[x][y] = 1
    global ans
    ans += 1
    dfs(x - 1, y)
    dfs(x + 1, y)
    dfs(x, y + 1)
    dfs(x, y - 1)

if __name__ == '__main__':
    n, m ,x, y= map(int, input().split())

    arr = []
    for i in range(n):
        str = input()
        arr.append(list(str))

    vis = [[0 for _ in range(m)] for _ in range(n)] # 判断是否走过,0为未走过,1为走过
    ans = 0

    dfs(x,y)


    print(ans)

连通块问题

题目地址:http://oj.hzjingma.com/p/29?view=classic

def dfs(grid, i, j):
    if not 0 <= i < len(grid) or not 0 <= j < len(grid[0]) or grid[i][j] == '.': return
    grid[i][j] = '.'
    dfs(grid, i + 1, j)
    dfs(grid, i, j + 1)
    dfs(grid, i - 1, j)
    dfs(grid, i, j - 1)
    dfs(grid, i + 1, j + 1)
    dfs(grid, i - 1, j + 1)
    dfs(grid, i - 1, j - 1)
    dfs(grid, i + 1, j - 1)

if __name__ == '__main__':
    n, m = map(int, input().split())

    arr = []
    for i in range(n):
        str = input()
        arr.append(list(str))

    ans = 0
    for i in range(n):
        for j in range(m):
            if arr[i][j] == 'W':
                dfs(arr,i, j)
                ans += 1
    print(ans)