leetcode - Insert Interval

题目描述：点击此处

/**
 * 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 Solution {
public:
  vector<Interval> insert(vector<Interval> &intervals, Interval newInterval) {
    // Start typing your C/C++ solution below
    // DO NOT write int main() function
    int maxN = 1000000000;
    vector<Interval> rlt;
    if (intervals.empty()){
      rlt.push_back(newInterval);
      return rlt;
    }
    intervals.push_back(newInterval);
    vector<Interval>::iterator vi;
    vector<Interval>::iterator pos =intervals.end()-1;
    for (vi=intervals.end()-1-1; vi+1!=intervals.begin(); vi--){
      if ((*vi).start>(*(vi+1)).start){
        pos = vi;
        Interval tmp = * vi;
        *vi = *(vi+1);
        *(vi+1) = tmp;
      }
    }
    for (vi = pos-1; vi+1!=intervals.begin(); vi--){
      if ( (*vi).end>=(*pos).start ){
        (*pos).start = (*vi).start;
        (*pos).end = (*pos).end > (*vi).end ? (*pos).end : (*vi).end;
        (*vi).start = maxN;
      }
      else break;
    }
    for (vi = pos+1; vi!=intervals.end(); vi++){
      if ( (*vi).start<=(*pos).end ){
        (*pos).end = (*pos).end > (*vi).end ? (*pos).end : (*vi).end;
        (*vi).start = maxN;
      }
      else break;
    }
    for (vi = intervals.begin(); vi!=intervals.end(); vi++){
      if ((*vi).start != maxN)
        rlt.push_back(*vi);
    }
    return rlt;
  }
};