B. New Year and Ascent Sequence：题目

小小思维题

#include <bits/stdc++.h>
using namespace std;
#define int long long
vector<int> a((int)6e5);
vector<int> b((int)6e5), c((int)6e5);
const int mod = 1e9 + 7;
signed main()
{int t;cin>>t;int cnt = 0;a[0] = 0x3f3f3f3f;while (t--){int n;cin>>n;int ff = 0;for (int i=1;i<=n;i++){cin>>a[i];if (a[i]>a[i-1]) ff = 1;}if (ff) c[cnt] = 0x3f3f3f3f,b[cnt] = -1;else c[cnt] = a[1],b[cnt] = a[n];cnt++;}sort(c.begin(),c.begin()+cnt);int res = 0;for (int i=0;i<cnt;i++){int k = lower_bound(c.begin(),c.begin()+cnt,b[i]+1)-c.begin();res+=cnt-k;}cout<<res<<endl;
}