1.小平方

代码

n = int(input())
count=0
def f(x)->bool: # 判断条件return True if x**2%n<n/2 else False
for i in range(1,n): # 遍历[1,n-1]，符合题意计数加一if f(i):count+=1
print(count)

2.3的倍数

代码

a = int(input())
b = int(input())
c = int(input())
if (a+b)%3==0 or (a+c)%3==0 or (b+c)%3==0:print('yes')
else:print('no')

3.格点

代码

count=0
for i in range(1,2022):for j in range(1,2022):if i*j<=2021:count+=1
print(count)