Python - `break` out of all loops [duplicate]

Question

You should put your loops inside a function and then return:

def myfunc():
    for i in range(1, 1001):
        for i2 in range(i, 1001):
            for i3 in range(i2, 1001):
                if i*i + i2*i2 == i3*i3 and i + i2 + i3 == 1000:
                    print i*i2*i3
                    return # Exit the function (and stop all of the loops)
myfunc() # Call the function

Using return immediately exits the enclosing function. In the process, all of the loops will be stopped.

You can raise an exception

try:
    for a in range(5):
        for b in range(5):
            if a==b==3:
                raise StopIteration
            print b
except StopIteration: pass

why not use a generator expression:

def my_iterator()
    for i in range(1, 1001):
        for i2 in range(i, 1001):
            for i3 in range(i2, 1001):
                yield i,i2,i3

for i,i2,i3 in my_iterator():
    if i*i + i2*i2 == i3*i3 and i + i2 + i3 == 1000:
        print i*i2*i3
        break

Not sure if this the cleanest way possible to do it but you could do a bool check at the top of every loop.

do_loop = True

for i in range(1, 1001):
    if not do_loop:
        break
    for i2 in range(i, 1001):
        # [Loop code here]
        # set do_loop to False to break parent loops