区间合并模板

#include <cstdio>
#include <algorithm>
#include <vector>
#define x first
#define y second
using namespace std;
typedef pair<int,int> PII;
int main()
{
    int t, n, m;
    vector<PII> p, tp;
    scanf("%d", &t);
    while(t--)
    {
        p.clear(), tp.clear();
        scanf("%d%d", &n, &m);
        for(int i = 0; i < m; i++)
        {
            int l, r;
            scanf("%d%d", &l, &r);
            tp.push_back({l, r});
        }
        sort(tp.begin(), tp.end());
        int st = 0, ed = 0;
        for(auto tt : tp)
        {
            if(ed < tt.x)
            {
                if(ed)
                    p.push_back({st, ed});
                st = tt.x, ed = tt.y;
            }
            else
                ed = max(ed, tt.y);
        }
        p.push_back({st, ed});
        for(auto tt : p)
            printf("%d %d\n",tt.x, tt.y);
        printf("\n");
    }
    return 0;
}

测试数据

2

3 3
1 3
2 4
5 7

3 1
1 2