def coin_change(coins, total):
    fewest_coins = 0
    cur_coin_index = 0
    cur_coin_value = coins[cur_coin_index]

    while total > 0:
        while total < cur_coin_value:
            cur_coin_index += 1
            cur_coin_value = coins[cur_coin_index]

        fewest_coins += total // cur_coin_value
        total %= cur_coin_value

    return fewest_coins


coins_1 = [10, 7, 1]
total_1 = 15
print(coin_change(coins_1, total_1))

coins_2 = [10, 7, 1]
total_2 = 18
print(coin_change(coins_2, total_2))