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problem_020_00.py
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##Counting Sundays
##Problem 19
##You are given the following information, but you may prefer to do
##some research for yourself.
##
##1 Jan 1900 was a Monday.
##Thirty days has September,
##April, June and November.
##All the rest have thirty-one,
##Saving February alone,
##Which has twenty-eight, rain or shine.
##And on leap years, twenty-nine.
##A leap year occurs on any year evenly divisible by 4,
##but not on a century unless it is divisible by 400.
##How many Sundays fell on the first of the month during
##the twentieth century (1 Jan 1901 to 31 Dec 2000)?
import numpy as np
import time
##
##DICTNUMB = {
## 1: "one",
## 2: "two",
## 3: "three",
## 4: "four",
## 5: "five",
## 6: "six",
## 7: "seven",
## 8: "eight",
## 9: "nine",
## 10: "ten",
## 11: "eleven",
## 12: "twelve",
## 13: "thirteen",
## 14: "fourteen",
## 15: "fifteen",
## 16: "sixteen",
## 17: "seventeen",
## 18: "eighteen",
## 19: "nineteen",
## 20: "twenty",
## 30: "thirty",
## 40: "forty",
## 50: "fifty",
## 100: "hundred",
## 1000: "onethousand"
## }
##DICTLENG = {}
##for i in DICTNUMB.keys():
## DICTLENG[i] = len(DICTNUMB[i])
##print(DICTLENG)
def sumstringnumber(number):
a = int(number)
b = str(a)
z = 0
for i in range(0, len(b)):
z += int(b[i])
return z
def collatz(number):
maxcount = 0
count = 1
dictcoll = {1:0}
dictmax = 0
for i in range(2,number):
a = i
while i > 1:
if i in dictcoll.keys():
count += dictcoll[i] -1
break
elif i%2==0:
i = i/2
count +=1
else:
i = 3*i + 1
count +=1
dictcoll[a] = count
maxcount = max(count, maxcount)
if count == maxcount:
dictmax = a
count = 1
return dictmax
def collatz2(number, maxv, cached):
number = int(number)
if number < maxv and cached[number] != None:
return cached[number]
elif number % 2 ==0:
temp = 1 + collatz2(number/2, maxv, cached)
else:
temp = 1 + collatz2(number*3 + 1, maxv, cached)
if number < maxv:
cached[number] = temp
return temp
def pyttrp(number):
listpossiblevalues =[]
for i in range(1,number+1):
listpossiblevalues.append(i)
listabc = []
## while (z + x + y) != number and y <((number)/2):
## z = int((x**2 + y**2)**0.5)
## for a in range(1, int(number/2+1)):
## x = a
## for b in range(1, int(number/2+1)):
## y=b
## z = int((x**2 + y**2)**0.5)
## if (z + x + y) == number and (z**2 == x**2 +y**2):
## print("helo",x,y,z, x+y+z, x**2, y**2,z**2)
## return (x,y,z)
for a in listpossiblevalues:
for b in listpossiblevalues:
c = number - (a+b)
if c**2 == a**2 + b**2:
listabc.append((a,b,c))
if a%100 ==0:
print(a)
listpossiblevalues.remove(a)
## for a in range(1, int(number)):
## for b in range(1, int(number)):
## c = number - (a+b)
## if c**2 == a**2 + b**2:
## listabc.append((a,b,c))
## print(a,b,c, a**2,b**2,c**2)
## print(a,b)
return listabc
def largestprod(string,length):
n = 1
for i in range(0,len(string)-(length)):
npd = np.arange(1,length+1)
for j in range(0, len(npd)):
npd[j] = int(string[i+j])
n = max(n,np.prod(npd))
return n
def smallestnumber(Nmax):
# find the list of prime numbers in range(Nmax)
listprimes2ton = primesfrom2to(Nmax)
# create an array for the factorization
valueeachprime = np.ones(len(listprimes2ton))
# create an array starting in number 2 ranging to Nmax, type float64
numbers = np.arange(2,Nmax, dtype=np.float64)
# factorize each number in the range. Update the factorization_array
for i in numbers:
while i not in listprimes2ton:
eachvalueprime = factorize(i, listprimes2ton)
for i in range(0,len(valueeachprime)):
valueeachprime[i] = max(valueeachprime[i],eachvalueprime[i])
valuearray = listprimes2ton**valueeachprime
# Calculate the least common multiple: with np.prod() I get an error or
# inconsistent results. I've tried several dtype = int, np.float64, but still get the error.
# So I use an alternative:
value = 1
for i in valuearray:
value = value * i
print(listprimes2ton)
print(valueeachprime)
return value
def factorize(n,listofprimes):
valueeachprime = np.zeros(len(listofprimes))
for i in range(1, len(listofprimes)):
while n >= listofprimes[i-1] and n % listofprimes[i-1] == 0:
n = n / listofprimes[i-1]
valueeachprime[i-1] = valueeachprime[i-1] + 1
return valueeachprime
def primesfrom2to(n):
""" Input n>=6, Returns a array of primes, 2 <= p < n """
sieve = np.ones(n/3 + (n%6==2), dtype=np.bool)
for i in range(1,int((n**0.5)/3+1)):
if sieve[i]:
k=3*i+1|1
sieve[ k*k/3 ::2*k] = False
sieve[k*(k-2*(i&1)+4)/3::2*k] = False
return np.r_[2,3,((3*np.nonzero(sieve)[0][1:]+1)|1)]
def calculatedivisors(maxlimit):
npdivisors = []
k = 0
while k == 0:
for i in range(2, int(maxlimit/2)):
if maxlimit % i == 0:
npd = np.ones(len(npdivisors), dtype=bool)
m = 0
try:
for j in npdivisors:
if i % j == 0:
npd[m] = False
break
m += 1
if npd.all():
npdivisors.append(i)
product = 1
for element in npdivisors:
product = element * product
if product == maxlimit:
k = 1
return npdivisors
except:
npdivisors.append(i)
print(npdivisors)
return npdivisors
def findpalind(Nmax):
list1 = []
for i in range(1, Nmax):
list1.append(i)
list1.reverse()
list2 = list1[:]
listpalind = set()
m = 0
while m == 0:
for i in list1:
for j in list2:
k = i * j
if str(k) == str(k)[::-1]:
## print("str(k) == str(k)[-1:1]", str(k), str(k)[::-1])
listpalind.add(k)
## print("appending ", k)
m = 1
## print(listpalind)
return listpalind
def isPal(s):
if len(s) <= 1:
return True
else:
return s == s[::-1]
def checkpals(Nmax):
val = 0
for i in range(Nmax,1,-1):
for j in range(Nmax,1,-1):
if isPal(str(i*j)) and i*j > val:
val = i*j
return val
def biggestprod(arrayn, howmanynumbers):
a = arrayn
nm = howmanynumbers
nmax = 0
for j in range(0, len(a[0])-nm):
for i in range(0,len(a)):
k = np.prod(a[i,j:j+nm])
nmax = max(nmax,k)
if nmax == k:
f = a[i,j:j+nm]
for i in range(0, len(a)-nm):
for j in range(0,len(a[0])):
k = np.prod(a[i:i+nm,j])
nmax = max(nmax,k)
if nmax == k:
f = a[i:i+nm,j]
for j in range(-len(a)+nm,len(a[0]-nm)):
m = np.diag(a,j)
for h in range(0, max(1,len(m)-nm)):
k = np.prod(m[h:h+nm])
nmax = max(nmax,k)
if nmax == k:
f = m[h:h+nm]
a = np.fliplr(a)
for j in range(-len(a)+nm,len(a[0]-nm)):
m = np.diag(a,j)
for h in range(0, max(1,len(m)-nm)):
k = np.prod(m[h:h+nm])
nmax = max(nmax,k)
if nmax == k:
f = m[h:h+nm]
return nmax,f
##
## while len(np.diag(a,j)) >= nm:
## print(j, np.diag(a,j))
## for h in range(0, len(np.diag(a,j))-nm):
## m = np.diag(a,h)
## k = np.prod(m[h:h+nm])
## print("m",m)
## print("m[h:h+nm]",m[h:h+nm])
## nmax = max(nmax,k)
##def calculatedivisorsnotconsecutive(n):
## npdivisors = 1 # The biggest divisor is n itself.
## # This is slower
#### a = n/2 + 1
#### b = 1
#### while b < a:
#### if n%b == 0:
#### npdivisors +=1
#### b +=1
####
## for i in range(1, int(n/2 +1)):
#### if n % i == 0:
#### npdivisors += 1
####
##
## return npdivisors
def calculatedivisorsnotconsecutive(n):
npdivisors = []
for i in range(1, int(n/2 +1)):
if i in npdivisors:
break
else:
if n % i == 0:
npdivisors.append(i)
npdivisors.append(n/i)
return npdivisors
def readfromfilesamplenames(filename):
fo = open(filename,"r")
list1 =[]
for line in fo:
list1.append(line.replace("\n", ""))
fo.close()
return list1
def sumbigarray(array, number):
n = number
h = array
k = len(h)
z = a = np.int64(0)
m = []
for i in range(0, k):
r = k-i-1
b = array[r] + a
m.append(b)
## print(str(h[r]),str(h[r])[:-3])
a = int(str(h[r])[:-3])
m.reverse()
print(m)
for i in range(0, n):
print(i, n, m[n-i-1])
print(int(m[n-i-1]),int(m[n-i-1])**i)
z += int(m[n-i-1])**int(i)
print(z)
return m, z
def getChildren(x,y,dictChildren):
"""Going through coordinates:
Each node has two children:
[
11 - 12 - 13 ... 1(n-1) - 1n
21 - 22 - 23 ... 2(n-1) - 2n
...
i1 - i2 - i3 ... i(n-1) - in
...
n1 - n2 - n3 ... n(n-1) - nn
]
The only available moves from one node
to its children are: right (xy -> x(y+1))
or: down (xy -> (x+1)y)
"""
x1,y1 = x, y+1 ## Right.
x2,y2 = x+1, y ## Down.
## print(x,y,x1,y1,x2,y2)
return x1,y1,x2,y2
def assignValueNode(x,y, maxx, maxy,dictChildren):
if (x,y) in dictChildren.keys():
## print(x,y,"returning from dictionary...", dictChildren[(x,y)])
return dictChildren[(x,y)]
elif x == maxx or y == maxy:
## print(x,y,"returning 1")
return 1
else:
## print(dictChildren)
x1,y1,x2,y2 = getChildren(x,y,dictChildren)
## print(dictChildren)
dictChildren[(x,y)] = assignValueNode(x1,y1,maxx,maxy,dictChildren) + assignValueNode(x2,y2,maxx,maxy,dictChildren)
return assignValueNode(x1,y1,maxx,maxy,dictChildren) + assignValueNode(x2,y2,maxx,maxy,dictChildren)
def calculateNumberLen(x):
st = 0
if x not in DICTLENG.keys():
## print(x, end=" ")
z = str(x)
a = len(z)
if a < 3: ## Number below 100, a == 2 because all single digits are in dict.
b = int(z[0]+"0")
if b in DICTLENG.keys():
st = DICTLENG[b] # length of the string.
## print(b, "is in DICTLENG and has a value of ", st)
else:
if z[0] == "0":
pass
## print(b, "is NOT in DICTLENG", end=" ")
elif z[0] != "8":
st = DICTLENG[int(z[0])] + 2 # ninety = nine + ty
## print(z, st)
else:
st = DICTLENG[int(z[0])] + 1 # eighty = eight + y
## print(z, st)
try:
c = int(z[1])
except:
c=0
if c != 0:
st += DICTLENG[c]
elif a == 3: ## Number between 100 and 1000 [100,1000)
st = DICTLENG[int(z[0])] + DICTLENG[100]
if x % 100 != 0:
st +=3 ## and
st += calculateNumberLen(int(z[1:3]))
else:
st = DICTLENG[x]
if x == 100:
st += 3
## print(x, st)
return st
def convertToPyramid(lista):
listb = []
for i in range(0,len(lista)):
listc = []
split = lista[i].split(" ")
for e in split:
listc.append(int(e))
listb.append(listc)
return listb
def calculateMaxPath(testArray,starting):
sample = testArray
startingi = starting[0]
startingj = starting[1]
valPath = {}
## print(valPath)
## Initialize the dictionary from the starting i,j
## to use it as the apex of the ensuing calculations:
valPath[startingi] = {x: [0,[]] for x in range(0,len(sample[startingi]))}
## print(valPath)
valPath[startingi][startingj] = [sample[startingi][startingj], [(startingi,startingj)]]
## print(valPath)
##
## print(valPath)
## print(valPath[startingi])
## print(valPath[startingi][startingj][0], "this is 1 ", valPath[startingi][startingj][1])
for i in range(startingi,len(sample)-1):
## print(i)
## print(valPath[i])
valPath[i+1] = {x:[0,[]] for x in range(0,len(sample[i+1]))}
## print(len(sample[i]), len(sample[i+1]))
for j in range(0, len(valPath[i+1].keys())):
if j == 0:
valPath[i+1][j] = [valPath[i][j][0] + sample[i+1][j], valPath[i][j][1] + [(i+1,j)]]
elif j >= len(valPath[i]):
valPath[i+1][j] = [valPath[i][j-1][0] + sample[i+1][j], valPath[i][j-1][1] + [(i+1,j)]]
else:
a1 = valPath[i][j][0] + sample[i+1][j]
a2 = valPath[i][j][1] + [(i+1,j)]
b1 = valPath[i][j-1][0] + sample[i+1][j]
b2 = valPath[i][j-1][1] + [(i+1,j)]
if a1 > b1:
input1 = a1
input2 = a2
else:
input1 = b1
input2 = b2
valPath[i+1][j] = [input1, input2]
return valPath
def countDayofWeek(dayoftheweek, dayofthemonth,startingday,startingmonth,startingyear,endday,endmonth,endyear):
""" Each year has 365 days, except leap years, that have 366
Key: 1 - Monday, 2 - Tuesday, 3 - Wednesday, 4 - Thursday, 5 - Friday
6 - Saturday, 7 - Sunday.
A non-leap year, has 52 weeks + 1 day.
A leap year has 52 weeks + 2 days.
"""
initialcalendar = (1,1,1900)
initialcalendarday = 1
startingcalendar = (startingday, startingmonth,startingyear)
endcalendar = (endday, endmonth, endyear)
## print(startingcalendar, endcalendar)
a = daysElapsed(dayoftheweek, dayofthemonth, startingcalendar)
b = daysElapsed(dayoftheweek, dayofthemonth, endcalendar)
print(b,a,b-a)
def daysElapsed(dayoftheweek,dayofthemonth,date):
day = date[0]
month = date[1]
year = date[2]
initialcalendar = (1,1,1900)
initialcalendarday = 1
## print(day,month,year,date)
yearspassed = year - initialcalendar[2]
monthspassed = month - initialcalendar[1]
dayspassed = day - initialcalendar[0]
monthsdays = {0:0, 1:31, 2:28, 3:31, 4:30, 5:31, 6:30, 7:31, 8: 31, 9:30,
10:31, 11:30, 12:31}
## print("here",dayspassed)
## from monthspassed to days passed:
if year % 400 == 0 or (year % 4 == 0 and year % 100 != 0):
monthsdays[2] = 29
else:
monthsdays[2] = 28
for i in range(0, monthspassed + 1):
dayspassed += monthsdays[i]
## from yearspassed to days passed:
for i in range(initialcalendar[2],year):
if i % 400 == 0 or (i % 4 == 0 and i % 100 != 0):
daysperyear = 366
elif (initialcalendar[2]-year) == 0:
pass
else:
daysperyear = 365
dayspassed += daysperyear
## print(dayspassed)
WEEKDAYS = [1,2,3,4,5,6,7]
countdaymonth = 1
countday = 1
countmonth = 1
yearcount = 1900
hits = 0
for m in range(1, dayspassed+1):
if yearcount % 400 == 0 or (yearcount % 4 == 0 and yearcount % 100 != 0):
monthsdays[2] = 29
else:
monthsdays[2] = 28
## print("a", "week", countday, dayoftheweek,"month", countdaymonth,dayofthemonth, countmonth,yearcount,m)
if countday == dayoftheweek and countdaymonth == dayofthemonth:
hits +=1
## print("hurray",countday, countdaymonth,m)
countday += 1
countdaymonth +=1
## print("b", countday,countdaymonth,countmonth,yearcount,m)
## input()
## reset the week counter:
if countday > len(WEEKDAYS):
countday = 1
if countdaymonth > monthsdays[countmonth]:
countdaymonth = 1
countmonth += 1
if countmonth > 12:
countmonth = 1
yearcount +=1
return hits
## The neat way of doing this:
## import datetime
## count = 0
## for y in range(1901,2001):
## for m in range(1,13):
## if datetime.datetime(y,m,1).weekday() == 6:
## count += 1
## print(count)
def main():
import math
from operator import mul
import functools
start = time.time()
## dayoftheweek, dayofthemonth,startingday,startingmonth,startingyear,endday,endmonth,endyear
## a = str(math.factorial(100))
##
## for b in a:
## c += int(b)
## print(c)
print(sum(int(x) for x in str(math.factorial(100))))
##
## print(sum(int(x) for x in str(functools.reduce(mul,range(1,101)))))
#### x = 0
## for i in str(math.factorial(100)):
## x += int(i)
## print(x)
## countDayofWeek(dayoftheweek = 7,dayofthemonth=1,startingday = 1,startingmonth=1,startingyear=1901,endday = 31,endmonth =12,endyear = 2000)
## a = readfromfilesamplenames("F:\\VirtualBOX\\DropBox\\Dropbox\\python\\Euler\\problem_018_data.txt")
#### print(a)
## testArray = convertToPyramid(a)
## b = calculateMaxPath(testArray,(0,0))
## listvals = {}
#### print(b)
## for e in b[len(b)-1].keys():
## listvals[b[len(b)-1][e][0]] = [b[len(b)-1][e][1]]
##
## print(max(listvals.keys()))
## print(listvals[max(listvals.keys()) ])
##
## t = 0
## for i in range(1,1001):
## t += calculateNumberLen(i)
## print(t)
## maxx = 20
## maxy = 20
## dictChildren = {(maxx,maxy):0}
## print(assignValueNode(0,0,maxx,maxy,dictChildren))
## maxv = 1000000
## print(sumstringnumber(2**1000))
## cached = [None] * maxv
## cached[1] = 1
## maxlen = 0
## maxind = None
## for item in range(1,maxv):
## a = collatz2(item,maxv, cached)
## if a > maxlen:
## maxlen = a
## maxind = item
## print(maxind)
##return dictcoll, dictmax, maxcount
## print(collatz(maxv))
## print(a)
## print(b)
## print(c)
## print(b[c])
## n = 6
## i = 4
## n = 1249975000 #6
## i = 50000 #4
## a = 0
## j = 50001
## for b in range(i,j-i):
## a +=b
## mi = n + i*(j-i) + a
## print(mi,a,calculatedivisorsnotconsecutive(mi))
## while len(calculatedivisorsnotconsecutive(n)) < 500:
## n = (n) + i
## i +=1
## print("The end")
## print(n, i)
## print(calculatedivisorsnotconsecutive(n))
##
## a = readfromfilesamplenames("F:\VirtualBOX\DropBox\Dropbox\python\Euler\problem_013_data.txt")
## b = []
## for e in a:
## b.append(int(e))
## c = np.array(b)
#### print(b,c)
##
## b = 0
## for item in a:
#### b += int(item)
#### print(b)
#### print("a", a)
## k = np.sum(c)
#### print("c",c)
## print("k",k)
##
#### b = np.ones((len(a), len(a[0])))
###### b = np.reshape(b, (len(str(a)),len(a[0])))
## for i in range(0,len(a)):
## for j in range(0, len(a[i])):
## b[i,j] = a[i][j]
## print(a)
## print(b)
## print("lena", len(a), "len(a[0])", len(a[0]),"lenb",len(b))
## h = np.sum(b,axis=1)
## print(h)
## testme = np.float64(0)
## for i in a:
## testme += np.float64(i)
## print("solution",i)
## print(len(str(i)))
## print("the first 10 digits...",str(i)[0:10:1])
## kk, k2 = sumbigarray(h, 10)
##
#### v = 0
## for i in range(0, len(h)):
## k = len(h)
## r = k-i-1
##
## z = (h[r])*(10**i)
## v += z
#### print(h[r],i,k,r,z, v)
## print("solution...", str(v)[0:11])
##print(z)
## a = np.loadtxt("F:\VirtualBOX\DropBox\Dropbox\python\Euler\problem_011_data.txt")
## maxvala, lista = biggestprod(a,4)
##
## print(maxvala)
## print(lista)
##
## k = primesfrom2to(2000000)
## print(k)
## print(len(k))
## s = 0
## for i in k:
## i = int(i)
## s = s+i
## print(s)
## print(np.sum(k, axis=0))
## palind = findpalind(1000)
## print(max(palind))
## minnum = smallestnumber(40)
## print(minnum)
end = time.time()
print(end -start)
main()