You are given coins of different denominations and a total amount of money amount. Write a function to compute the fewest number of coins that you need to make up that amount. If that amount of money cannot be made up by any combination of the coins, return -1
.
Example 1:
coins = [1, 2, 5]
, amount = 11
return 3
(11 = 5 + 5 + 1)
Example 2:
coins = [2]
, amount = 3
return -1
.
Note:
You may assume that you have an infinite number of each kind of coin.
Credits:
Special thanks to @jianchao.li.fighter for adding this problem and creating all test cases.
class Solution(object):
def coinChange(self, coins, amount):
if amount == 0:
return 0
res = [-1] * (max(max(coins),amount) + 1)
for i in xrange(1,amount+1):
if i not in coins:
minn = 99999999
for j in coins:
if (i-j) < amount and res[i-j] > -1:
#print i-j
#minn = min(res[i-j]+1,minn) #为什么用这句会超时呢!?
if res[i-j] + 1< minn:
minn = res[i-j] + 1
if minn != 99999999:
res[i] = minn
else:
res[i] = 1
return res[amount]