from lpython import i32, str

def test_list_iter():

lst: list[i32] = [1, 2, 3, 4, 5]

total: i32 = 0

x: i32

for x in lst:

total += x

assert total == 15

print("list iteration ok")

def test_string_iter():

s: str = "hello"

chars: list[str] = []

ch: str

for ch in s:

chars.append(ch)

assert chars == ["h", "e", "l", "l", "o"]

print("string iteration ok")

def test_range_iter():

sum1: i32 = 0

i: i32

for i in range(5):

sum1 += i

assert sum1 == 10

print("range iteration ok")

def test_nested():

mat: list[list[i32]] = [[1, 2], [3, 4]]

total: i32 = 0

row: list[i32]

elem: i32

for row in mat:

for elem in row:

total += elem

assert total == 10

print("nested iteration ok")

def test_empty():

lst2: list[i32] = []

count: i32 = 0

_: i32

for _ in lst2:

count += 1

assert count == 0

print("empty iteration ok")

def test_single():

lst3: list[i32] = [42]

val: i32 = 0

x: i32

for x in lst3:

val = x

assert val == 42

print("single iteration ok")

def test_step_range():

sum2: i32 = 0

i: i32

for i in range(0, 10, 2):

sum2 += i

assert sum2 == 20

print("step range ok")

def test_negative_step():

sum3: i32 = 0

i: i32

for i in range(10, 0, -2):

sum3 += i

assert sum3 == 30

print("negative step range ok")

def test_while_loop():

i: i32 = 0

total: i32 = 0

while i < 5:

total += i

i += 1

assert total == 10

print("while loop ok")

# Main

test_list_iter()

test_string_iter()

test_range_iter()

test_nested()

test_empty()

test_single()

test_step_range()

test_negative_step()

test_while_loop()

print("All tests passed")