Loops

def solve1(n):
    x = 0;
    for a in range(n, 0, -1):
        for b in range(1, a+1):
            x += b
        # print(x)
    return x;

def solve2(n):
    x = 0;
    for a in range(n-2, 0, -1):
        for b in range(1, a+1):
            x += b
        # print(x)
    return x +  (n*n);

# Best Solution
def solve3(n):
    x = 0
    for a in range(n, 0, -2):
        x += a*a
    return x;

# Recursive Solution
def solve4(n):
    if (n > 0):
        return n*n + solve4(n-2)
    return 0

def main():
    number = input()
    if (0 <= int(number) <= 1000000):
        print(solve3(int(number)))

main()

# Solve(5)
# 1+2+3+4+5 = 15
# 1+2+3+4   = 10
# 1+2+3     = 6
# 1+2       = 3
# 1         = 1
#             --
#             35

# Solve3(5)
# 5*5       = 25
# 3*3       = 9
# 1*1       = 1
#           --
#           35

Test 1

Verdict: ACCEPTED

Test 2

Verdict: ACCEPTED

Test 3

Verdict: ACCEPTED

Test 4

Verdict: ACCEPTED

Test 5

Verdict: ACCEPTED

Test 6

Verdict: ACCEPTED

Test 7

Verdict: ACCEPTED

Test 8

Verdict: ACCEPTED

Test 9

Verdict: ACCEPTED

Test 10

Verdict: ACCEPTED

Test 11

Verdict: ACCEPTED

Test 12

Verdict: ACCEPTED

Test 13

Verdict: ACCEPTED

Test 14

Verdict: ACCEPTED

Test 15

Verdict: ACCEPTED

Test 16

Verdict: ACCEPTED

Test 17

Verdict: ACCEPTED

Test 18

Verdict: ACCEPTED

Test 19

Verdict: ACCEPTED

Test 20

Verdict: ACCEPTED