区间调度问题

#include<iostream>
#include<algorithm>
using namespace std;
const int maxn = 10000;
int s[maxn],t[maxn];
pair<int, int> a[maxn];
int main()
{
    int n;
    cin >> n;
    for(int i=0; i<n; i++)
        cin >> s[i];
    for(int i=0; i<n; i++)
        cin >> t[i];

    for(int i=0; i<n; i++)
    {
        a[i].first = t[i];
        a[i].second = s[i];
    }
    sort(a, a+n);
    int ans = 0, t = 0;
    for(int i=0; i<n; i++)
    {
        if(t<a[i].second)
        {
            ans++;
            t = a[i].first;
        }
    }
    cout << ans << endl;
    return 0;
}
/*
5
1 2 4 6 8
3 5 7 9 10
3

Process returned 0 (0x0)   execution time : 8.684 s
Press any key to continue.
*/