For 循环在一次输出后停止

Question

Make an integer of product, multiplier and multiplicand

def fac(n) :
  f = []
  for i in range(2,int(n/2)) :
    if n % i == 0 : f.append(i)
  return f
def check(n) :
  g = []
  for j in fac(n) :
    g.append(n)
    g.append(j)
    g.append(int(n/j))
    x = int("".join(map(str, g)))
    return x
print (check(28))

gives output 28214 which is expected but it gives only one output stops after that why doesn't return next 2847(28,4,7) ?

Answer 1

Return exits the function, which exits the loop. You could try printing x in the loop or build up and then return x outside of the loop.

Answer 2

for j in fac(n) :
    g.append(n)
    g.append(j)
    g.append(int(n/j))
    x = int("".join(map(str, g)))
    return x

The return x is aligned with the iterator; if you want it to return multiple values, you'd want to move it to the left so that it aligns with the for j loop.

I also think you want to return list g as opposed to x.

Answer 3

Well You need to simply change the return in check function to yield thereby converting it to a generator and we can use the next function to iterate through the output

def fac(n) :
  f = []
  for i in range(2,int(n/2)) :
    if n % i == 0 : f.append(i)
  return f

def check(n) : 
  for j in fac(n) :
    g=[]
    g.append(n)
    g.append(j)
    g.append(int(n/j))
    x = int("".join(map(str, g)))
    yield x
print("using for loop")
#print (check(28))
for i in check(28):
    print(i)


print("Using next function")
n=check(28)
print(next(n))
print(next(n))
print(next(n))

OUTPUT

using for loop
28214
2847
2874
Using next function
28214
2847
2874