[C++知识库]C++之set find结构体对象

以下面的例子作说明，leetcode中的365水壶问题：

class Solution {
public:
    struct status{
        int left;
        int right;
    };
class statusSort {
public:
	//重点
    bool operator() (const status &a, const status &b) const {
        if(a.left!=b.left)return a.left<b.left;
        else return a.right<b.right;
    }
};
    bool canMeasureWater(int jug1Capacity, int jug2Capacity, int targetCapacity) {
        stack<status>s;
        set<status,statusSort>st;
        s.push(status{0,0});
        while(!s.empty()){
            status temp=s.top();
            s.pop();
            int l=temp.left,r=temp.right;
            if(l==targetCapacity||r==targetCapacity||(l+r)==targetCapacity)return true;
            set<status,statusSort>::iterator it=st.find(temp);
            if(it!=st.end())continue;
            st.insert(temp);
            s.push(status{jug1Capacity,r});
            s.push(status{l,jug2Capacity});
            s.push(status{l,0});
            s.push(status{0,r});
            s.push(status{l-min(l,jug2Capacity-r),r+min(l,jug2Capacity-r)});
            s.push(status{l+min(r,jug1Capacity-l),r-min(r,jug1Capacity-l)});

        }
        return false;
    }
};