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You are playing a computer game, where you lead a party of m soldiers. Each soldier is characterised by his agility ai.
The level you are trying to get through can be represented as a straight line segment from point 0 (where you and your squad is initially located) to point n+1 (where the boss is located).
The level is filled with k traps. Each trap is represented by three numbers li, ri and di. li is the location of the trap, and di is the danger level of the trap: whenever a soldier with agility lower than di steps on a trap (that is, moves to the point li), he gets instantly killed. Fortunately, you can disarm traps: if you move to the point ri, you disarm this trap, and it no longer poses any danger to your soldiers. Traps don’t affect you, only your soldiers.
You have t seconds to complete the level — that is, to bring some soldiers from your squad to the boss. Before the level starts, you choose which soldiers will be coming with you, and which soldiers won’t be. After that, you have to bring all of the chosen soldiers to the boss. To do so, you may perform the following actions:
Note that after each action both your coordinate and the coordinate of your squad should be integers.
You have to choose the maximum number of soldiers such that they all can be brought from the point 0 to the point n+1 (where the boss waits) in no more than t seconds.
Input
The first line contains four integers m, n, k and t (1≤m,n,k,t≤2⋅105, n<t) — the number of soldiers, the number of integer points between the squad and the boss, the number of traps and the maximum number of seconds you may spend to bring the squad to the boss, respectively.
The second line contains m integers a1, a2, …, am (1≤ai≤2⋅105), where ai is the agility of the i-th soldier.
Then k lines follow, containing the descriptions of traps. Each line contains three numbers li, ri and di (1≤li≤ri≤n, 1≤di≤2⋅105) — the location of the trap, the location where the trap can be disarmed, and its danger level, respectively.
Output
Print one integer — the maximum number of soldiers you may choose so that you may bring them all to the boss in no more than t seconds.
Sample Input
5 6 4 14
1 2 3 4 5 1 5 2 1 2 5 2 3 5 3 5 3Sample Output
3
AC代码:
#includeusing namespace std;#define SIS std::ios::sync_with_stdio(false),cin.tie(0),cout.tie(0)#define endl '\n'const int MAXN = 2e5+5;int m,n,k,t;int a[MAXN],l[MAXN],r[MAXN],d[MAXN];bool compare(int x){ int y=a[m-x]; vector > vec; for(int i=0;i y) vec.push_back(make_pair(l[i],r[i])); sort(vec.begin(),vec.end()); int res=n+1,end=0; for(auto lr : vec) { res+=2*max(0,lr.second-max(lr.first,end)); end=max(end,lr.second); } return (res<=t);}int main(){ SIS; cin >> m >> n >> k >> t; for(int i=0;i > a[i]; sort(a,a+m); for(int i=0;i > l[i] >> r[i] >> d[i],l[i]--; int st=0,ed=m+1; while(ed-st>1) { int mid=(st+ed)>>1; if(compare(mid)) st=mid; else ed=mid; } cout << st << endl; return 0;}
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