Tasks

A. Buying Sweets … Simple print modulus (=changes) result

x = int(input())
a = int(input())
b = int(input())
print((x-a)%b)

B. Coins … This takes N^3, and it’s much costly. And obviously there is a room for improvement.

a = int(input())
b = int(input())
c = int(input())
x = int(input())
count = 0
for i in range(a+1):
for j in range(b+1):
for k in range(c+1):
if 500 * i + 100 * j + 50 * k == x:
count += 1
print(count)

C. Candies … Iterate index one by one, so the cost is N.

n = int(input())
rows = []
for i in range(2):
rows.append(list(map(int, input().split())))
max_candies = 0
for j in range(n):
if sum(rows[0][:j+1]) + sum(rows[1][j:]) > max_candies:
max_candies = sum(rows[0][:j+1]) + sum(rows[1][j:])
print(max_candies)

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