题目链接
贪心
class Solution {public boolean lemonadeChange(int[] bills) {if(bills[0] == 10 || bills[0] == 20 || bills[1] == 20){return false;}int count5 = 1;int count10 = 0;for(int i = 1; i < bills.length; i++){if(bills[i] == 5){count5++;}if(bills[i] == 10){count10++;if(count5 >= 1){count5--;}else{return false;}} if(bills[i] == 20){if(count10 >= 1){if(count5 >= 1){count10--;count5--;}else{return false;}}else{if(count5 >= 3){count5 = count5 - 3;}else{return false;}}}}return true;}
}