***Leetcode 435. Non-overlapping Intervals

Posted 2022-12-07 Z-Pilgrim

https://leetcode.com/problems/non-overlapping-intervals/description/

很不错的题 跟课程规划那个题有点相似

bool cmp( const Interval& a , const Interval& b ) 
    if (a.start != b.start) return a.start < b.start;
    return a.end < b.end;


bool judge( Interval&a, Interval&b ) 
    if (a.end <= b.start || a.start >= b.end) return true;
    else return false;


class Solution 
public:
    int eraseOverlapIntervals(vector<Interval>& intervals) 
        if (intervals.size()<=1) return 0;
        sort( intervals.begin(), intervals.end(), cmp );
        Interval last = intervals[0];
        int ret = 0;
        for (int i = 1; i < intervals.size(); i++) 
            if (!judge(last, intervals[i])) 
                ret ++;
                if (last.end > intervals[i].end) last = intervals[i];
             else 
                last = intervals[i];
            
        
        return  ret;
    
;