352.md

进一步熟悉了STL吧 map的item类型是pair<const T1, T2>

lower_bound要提防还有等于的情况

STL不是随机就不能用-1

修改map部分写的还是太复杂，思路不清楚de了半天的bug

/**
 * Definition for an interval.
 * struct Interval {
 *     int start;
 *     int end;
 *     Interval() : start(0), end(0) {}
 *     Interval(int s, int e) : start(s), end(e) {}
 * };
 */
class SummaryRanges {
public:
    map<int, int> ans;
    /** Initialize your data structure here. */
    SummaryRanges() {
        
    }
    
    void addNum(int val) {
        if(ans.size() == 0){
            ans[val] = val;
        }
        auto i = ans.lower_bound(val), pre = i;
        if(i != ans.begin()){
            pre = --i;
            i++;
        }
        if(i == ans.end()){
            if(pre->second < val){
                if(val == pre->second + 1)
                    pre->second ++;
                else 
                    ans[val] = val;
            }
        }
        else if(i == ans.begin()){
            if(i->first == val)
                return;
            if(i->first == val+1){
                ans[val] = i->second;
                ans.erase(val+1);
            }
            else ans[val] = val; 
        }
        else{
            if(val == i->first || val <= pre->second) return;
            else if(val == i->first-1 && val == pre->second+1){
                pre->second = i->second;
                ans.erase(i);
            }
            else if(val == i->first-1){
                ans[val] = i->second;
                ans.erase(i);
            }
            else if(val == pre->second+1){
                pre->second++;
            }
            else ans[val] = val;
        }
    }
    
    vector<Interval> getIntervals() {
        vector<Interval> a;
        for(auto it = ans.begin(); it != ans.end(); ++it)
        {
            a.push_back(Interval(it->first, it->second));
        }
        return a;
    }
};

/**
 * Your SummaryRanges object will be instantiated and called as such:
 * SummaryRanges obj = new SummaryRanges();
 * obj.addNum(val);
 * vector<Interval> param_2 = obj.getIntervals();
 */