Python Программа Нет Выходной

Question

Проблема заключается в том, как:

The primes 3, 7, 109, and 673, are quite remarkable. By taking any two primes and concatenating them in any order the result will always be prime. For example, taking 7 and 109, both 7109 and 1097 are prime. The sum of these four primes, 792, represents the lowest sum for a set of four primes with this property. Find the lowest sum for a set of five primes for which any two primes concatenate to produce another prime.

Теперь Ниже приводится программа, которая не дает никаких выходных данных в списке результатов. Пожалуйста, помогите

LIMIT = 20000 

prima = [] #empty list 

def Bsearch(lsta,low,high,search): #Binary search function to search a prime number 
    if low>high: 
     return 0 
    else: 
     mid = int((low+high)/2) 

     if search<lsta[mid]: 
      Bsearch(lsta,low,mid-1,search) 
     if search>lsta[mid]: 
      Bsearch(lsta,mid+1,high,search) 
     if search==lsta[mid]: 
      return 1 
    return 0 

def primes(LIMIT): #sieve to create prime numbers upto LIMIT 
    dic = {} #empty dictionary 
    for i in range(2,LIMIT): 
     dic[i] = 1 
    for i in range(2,LIMIT): 
     for j in range(i,LIMIT): 
      if i*j>LIMIT: 
       break 
      dic[i*j] = 0 
    for i in range(2,LIMIT): 
     if dic[i]==1: 
      prima.append(i) 

primes(LIMIT) 

result = [] 

for i in range(0,len(prima)): 
    print(str((i/len(prima)*100))+"% list passed") 

    tempa = [] 
    tempa.append(prima[i]) 
    count = 0 
    for j in range(i+1,len(prima)): 
     c1 = int(str(prima[j])+str(prima[i])) #first combination 
     c2 = int(str(prima[i])+str(prima[j])) #second combination 
     if(Bsearch(prima,0,len(prima)-1,c1) and Bsearch(prima,0,len(prima)-1,c2)): 
      print("small success : "+str(count)) 
      tempa.append(prima[j]) 
      count +=1 
     if(count==4): 
      result.append(tempa) 
      print("success!") 
      break 

for item in result: 
    print(item) 

Answer 1

LIMIT = 20000 

prima = [] #empty list 

def Bsearch(lsta,low,high,search): #Binary search function to search a prime number 
    if low>high: 
     return 0 
    else: 
     mid = int((low+high)/2) 

     if search<lsta[mid]: 
      Bsearch(lsta,low,mid-1,search) 
     if search>lsta[mid]: 
      Bsearch(lsta,mid+1,high,search) 
     if search==lsta[mid]: 
      return 1 
    return 0 

def primes(LIMIT): #sieve to create prime numbers upto LIMIT 
    dic = {} #empty dictionary 
    for i in range(2,LIMIT): 
     dic[i] = 1 
    for i in range(2,LIMIT): 
     for j in range(i,LIMIT): 
      if i*j>LIMIT: 
       break 
      dic[i*j] = 0 
    for i in range(2,LIMIT): 
     if dic[i]==1: 
      prima.append(i) 

primes(LIMIT) 

result = [] 

Answer 2

Поскольку ваш поиск рекурсивен, вы должны возвращать результаты поиска.

def Bsearch(lsta,low,high,search): #Binary search function to search a prime number 
    retval = 0 
    if low>high: 
    retval = 0 
    else: 
    mid = int((low+high)/2) 

    if search == lsta[mid]: 
     # Make this test first as allows it to exit at once with success 
     retval = 1 
    elif search<lsta[mid]: 
     retval = Bsearch(lsta,low,mid-1,search) 
    else:  # search>lsta[mid] Since only 3 choices elif not needed 
     retval = Bsearch(lsta,mid+1,high,search) 
    return retval 

Answer 3

LIMIT = 20000 

prima = [] #empty list 

def Bsearch(lsta,low,high,search): #Binary search function to search a prime number 
    if low>high: 
     return 0 
    else: 
     mid = int((low+high)/2) 

     if search<lsta[mid]: 
      Bsearch(lsta,low,mid-1,search) 
     if search>lsta[mid]: 
      Bsearch(lsta,mid+1,high,search) 
     if search==lsta[mid]: 
      return 1 
    return 0 

def primes(LIMIT): #sieve to create prime numbers upto LIMIT 
    dic = {} #empty dictionary 
    for i in range(2,LIMIT): 
     dic[i] = 1 
    for i in range(2,LIMIT): 
     for j in range(i,LIMIT): 
      if i*j>LIMIT: 
       break 
      dic[i*j] = 0 
    for i in range(2,LIMIT): 
     if dic[i]==1: 
      prima.append(i) 

primes(LIMIT) 

result = []