Codeforces 356A

这题有个注意的地方，就是对集合边读边删除的时候，应该尤为注意。。   my_set.erase(it++)

 1 #include <iostream>

 2 

 3 #include <cstring>

 4 #include <set>

 5 

 6 using namespace std;

 7 

 8 int color[300005];

 9 

10 int main(){

11     int n, m;

12     while (cin >> n >> m) {

13         set<int> my_set;

14         for (int i = 1; i <= n; i++) {

15             my_set.insert(i);

16         }

17         memset(color, 0, sizeof(color));

18 

19         for (int i = 0; i < m; i++) {

20             int l, r, x;

21             cin >> l >> r >> x;

22             set<int>::iterator it;

23             it = my_set.lower_bound(l);

24             while (it != my_set.end()) {

25                 if ((*it) > r) {

26                     break;

27                 }

28                 if ((*it) == x) {

29                     it++;

30                     continue;

31                 }

32                 color[(*it)] = x;

33                 my_set.erase(it++);

34                 /* it++; */

35             }

36         }

37         for (int i = 1; i <= n; i++) {

38             cout << color[i] << (i==n ? '\n' : ' ');

39         }

40     }

41 

42     return 0;

43 }