12 Задание Егэ

for x in range(50):
    s = '1' * 10 + '2' * x
    while '21 ' in s:
        s = s.replace('21', '6', 1)
    if (s.count('1') + s.count('2') * 2 ) == 50:
        print(x)
        break

def change_and_check(s):
    s_old = s
    while '21' in s:
        s = s.replace('21', '6')
    if sum(map(int, s)) == 50:
        print(s_old.count('2'))
        return True
    return False
 
 
a = '21111111111'
 
while True:
    a_new = a + '2'
    if change_and_check(a_new):
        break
    a_new = a + '22'
    if change_and_check(a_new):
        break
 
    tmp = a.rfind('21')
    a = a[:tmp + 2] + '2' + a[tmp + 2:]
    if change_and_check(a):
        break

res = 20
for d6 in range(0, 9, 2):
    d2 = (50 - 6*d6 - (10 - d6))//2
    d1 = 10 - d6
    s = '21'*d6 + '1'*d1 + '2'*d2
    s = s.replace('21', '6')
    res = min(res, d2 + d6) 
print(res)

res = []
for a in range(10+1):
    for b in range(50//2+1):
        if a*1 + b*2 + (10-a)*6 == 50:
            res.append( b+10-a )
print( min(res) )

from random import shuffle
 
 
m = float('inf')
for i in range(1, 5000):
    for x in range(1, 50):
        st = list(('1' * 10) + ('2' * x))
        k2 = st.count('2')
        shuffle(st)
        st = "".join(st)
        while '21' in st:
            st = st.replace('21', '6', 1)
        if sum(map(int, st)) == 50:
            m = min(m, k2)
print(m)