10贪心：柠檬水找零

10贪心：柠檬水找零

860. 柠檬水找零

class Solution {
    public boolean lemonadeChange(int[] bills) {
        //每一次都可以找0 可以正确找0
        //分三种情况 5 10 15
        int banlanceFive = 0;
        int banlanceTen = 0;
        int banlanceTwenty = 0;//其实可以不记录收的20，因为不可能找20
        for(int i = 0; i < bills.length; i++) {
            if(bills[i] == 5) banlanceFive++;
            if(bills[i] == 10) {
                banlanceTen++;
                banlanceFive--;
            }
            if(bills[i] == 20) {
                banlanceTwenty++;
                if(banlanceTen > 0) banlanceTen--;
                else banlanceFive = banlanceFive - 2;

                banlanceFive--;
            }
            if(banlanceTen < 0 || banlanceFive < 0) return false;
        }
        return true;
    }
}
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