[🐉 백준 9단계] 수학 2

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백준 9단계

수학 2

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1978

n=input()
l=list(map(int, input().split()))
answer = 0

for i in l:
  count = 0
  for j in range(1, i+1):
    if i == 1:
      break

    if i%j == 0:
      count += 1

  if count == 2:
    answer += 1


print(answer)

 

2581

import math

while True:
  n = int(input())

  if n == 0:
    break
  
  count = 0
  for i in range(n+1, 2*n+1):

    if i == 1:
      continue

    elif i == 2:
      count += 1
      continue

    else:
      for j in range(2, int(math.sqrt(i))+1):
        if i%j == 0:
          break
      else:
        count += 1

  print(count)

 

1929

def sosu(n):
  import math
  for i in range(2, int(math.sqrt(n))+1):
    if n%i == 0:
      return False
  return True


m, n = map(int, input().split())

for i in range(m, n+1):
  if i == 1:
    continue
  if sosu(i) == True:
    print(i)

 

4948

import math

def IsPrime(num):
    a = int(math.sqrt(num))
    if num == 1:
        return False
    else:
        for i in range(2, a+1):
            if num % i == 0: 
                return False
        return True

Num_list = list(range(2,246912))
Sort_list = []
for i in Num_list:
    if IsPrime(i):
         Sort_list.append(i)

while True:
    n = int(input())
    if n == 0:
        break
    cnt = 0
    for i in Sort_list:
        if n < i <= n*2:
            cnt += 1
    print(cnt)  

 

9020

ch=[0]*10001
sosu=[0]*10001
for i in range(2,10001):
    if ch[i]==0:
        sosu[i]=i
        for j in range(i,10001,i):
            ch[j]=1

n=int(input())
for _ in range(n):
    i=int(input())
    left=i//2
    while left>1:
        right=i-left
        if sosu[left]>0 and sosu[right]>0:
            res=[sosu[left], sosu[right]]
            break
        else:
            left-=1
        
    print(res[0], res[1])

 

1085

x, y, w, h = list(map(int,input().split()))
print(min([x, y, w-x, h-y]))

 

3009

xl = []
yl = []
for _ in range(3):
  x,y = map(int,input().split())

  if x in xl:
    xl.remove(x)
  else:
    xl.append(x)

  if y in yl:
    yl.remove(y)
  else:
    yl.append(y)
print(xl[0], yl[0])

 

4153

while True:
  l = list(map(int, input().split()))

  h = max(l)
  l.remove(h)
  x = l[0]
  y = l[1]
  
  if x == 0 and y == 0 and h == 0:
    break

  if x**2 + y**2 == h**2:
    print('right')
  else:
    print('wrong')

 

3053

pi = 3.14159265359
r = int(input())

print(pi*(r**2))
print(2*(r**2))

 

1002

test = int(input())

for _ in range(test):
    x1, y1, r1, x2, y2, r2 = map(int, input().split())
    distance = (((x1 - x2) ** 2) + ((y1 - y2) ** 2)) ** 0.5
    
    if x1 == x2 and y1 == y2:
        if r1 == r2:
            print(-1)
        else:
            print(0)
        continue
    
    if r1 > distance + r2 or r2 > distance + r1 or distance > r1 + r2:
        print(0)
    elif r1 == distance + r2 or r2 == distance + r1 or r1 + r2 == distance:
        print(1)
    else:
        print(2)