num = 0
for i in range(1, 2021):
i = str(i)
num += i.count('2')
print(num)
答案: 624
num = 0
# 辗转相除
def func(a, b):
x = a % b
while x != 0:
a = b
b = x
x = a % b
return b
for i in range(1, 2021):
for j in range(1, 2021):
if func(i, j) == 1:
num += 1
print(num)
答案:2481215
dir = 0 # 0代表向右,1代表向下
a = [[0 for i in range(100)] for j in range(100)]
x, y = 0, 0
num = 1
while True:
if x == 19 and y == 19:
break
while dir == 0:
x, y = x, y+1
num += 1
while y != 0:
x += 1
y -= 1
num += 1
if x == 19 and y == 19:
print(num)
break
dir = 1
while dir == 1:
x, y = x+1, y
num += 1
while x != 0:
x -= 1
y += 1
num += 1
if x == 19 and y == 19:
print(num)
break
dir = 0
答案: 761
year = 2000
month = 1
day = 1
week = 6
res = 0
dateday = [0,31,28,31,30,31,30,31,31,30,31,30,31]
# 闰年判断
def run(year):
if year % 4 == 0 and year % 100 != 0:
return True
elif year % 400 == 0:
return True
else:
return False
while year != 2020 or month != 10 or day != 1:
if run(year):
dateday[2] = 29
else:
dateday[2] = 28
day += 1
week = (week+1)%7
if day > dateday[month]:
day = 1
month += 1
if month > 12:
month = 1
year += 1
if day == 1 or week == 1:
res += 1
res += 1
res += 2
print(res)
答案: 8879
这个可以数发光的个数:
1 : 7种
2: 10种
3: 16种
4: 20种
5: 19种
6: 7种
7: 1种
ans = 7 + 10 + 16 + 20 + 19 + 7 + 1 = 80
一共80种
n = int(input())
num1 = 0
num2 = 0
for i in range(n):
stu = int(input())
if stu >= 60:
num1 += 1
if stu >= 85:
num2 += 1
print('{:d}%'.format(round(num1/n*100)))
print('{:d}%'.format(round(num2/n*100)))
from calendar import isleap
n = int(input())
def check(year):
month = int(year[:2])
day = int(year[2:4])
year = int(year)
if 1 <= month <= 12:
if month == 2:
if isleap(year):
if day <= 29:
return True
else:
return False
else:
if day <= 28:
return True
else:
return False
if month in [1,3,5,7,8,10,12]:
if day <= 31:
return True
else:
return False
else:
if day <= 30:
return True
return False
return False
arr1 = []
arr2 = []
for i in range(1000, 9999):
x1 = str(i)[::-1]
x2 = (str(i)[:2]+str(i)[:2])[::-1]
if check(x1) and int(x1[::-1]+x1)>n:
arr1.append(int(x1[::-1]+x1))
if check(x2) and int(x2[::-1]+x2)>n:
arr2.append(int(x2[::-1]+x2))
print(arr1[0])
print(arr2[0])
s = input()
n = len(s)
res = 0
left = 0
right = 0
while left < n:
if right == n:
left += 1
right = left
right += 1
s_ = set(s[left:right])
res += len(s_)
print(res)
n = int(input())
li = []
for i in range(n):
li.append(list(map(int, input().split())))
res = 2
node = []
for i in range(1, n):
for j in range(i):
if li[i][0] != li[j][0]:
x = (li[i][1] - li[j][1]) / (li[j][0] - li[i][0])
y = li[j][0] * x + li[j][1]
if [x, y] in node:
pass
else:
node.append([x, y])
res += len(node) + 1
node = []
print(res)