二分+尺取
作者：互联网
题意：https://vjudge.net/contest/336100#problem/B
HDU6231
1 #define IOS ios_base::sync_with_stdio(0); cin.tie(0);
2 #include <cstdio>//sprintf islower isupper
3 #include <cstdlib>//malloc exit strcat itoa system("cls")
4 #include <iostream>//pair
5 #include <fstream>//freopen("C:\\Users\\13606\\Desktop\\草稿.txt","r",stdin);
6 #include <bitset>
7 //#include <map>
8 //#include<unordered_map>
9 #include <vector>
10 #include <stack>
11 #include <set>
12 #include <string.h>//strstr substr
13 #include <string>
14 #include <time.h>//srand(((unsigned)time(NULL))); Seed n=rand()%10 - 0~9;
15 #include <cmath>
16 #include <deque>
17 #include <queue>//priority_queue<int, vector<int>, greater<int> > q;//less
18 #include <vector>//emplace_back
19 //#include <math.h>
20 //#include <windows.h>//reverse(a,a+len);// ~ ! ~ ! floor
21 #include <algorithm>//sort + unique : sz=unique(b+1,b+n+1)-(b+1);+nth_element(first, nth, last, compare)
22 using namespace std;//next_permutation(a+1,a+1+n);//prev_permutation
23 //******************
24 int abss(int a);
25 int lowbit(int n);
26 int Del_bit_1(int n);
27 int maxx(int a,int b);
28 int minn(int a,int b);
29 double fabss(double a);
30 void swapp(int &a,int &b);
31 clock_t __STRAT,__END;
32 double __TOTALTIME;
33 void _MS(){__STRAT=clock();}
34 void _ME(){__END=clock();__TOTALTIME=(double)(__END-__STRAT)/CLOCKS_PER_SEC;cout<<"Time: "<<__TOTALTIME<<" s"<<endl;}
35 //***********************
36 #define rint register int
37 #define fo(a,b,c) for(rint a=b;a<=c;++a)
38 #define fr(a,b,c) for(rint a=b;a>=c;--a)
39 #define mem(a,b) memset(a,b,sizeof(a))
40 #define pr printf
41 #define sc scanf
42 #define ls rt<<1
43 #define rs rt<<1|1
44 typedef long long ll;
45 const double E=2.718281828;
46 const double PI=acos(-1.0);
47 //const ll INF=(1LL<<60);
48 const int inf=(1<<30);
49 const double ESP=1e-9;
50 const int mod=(int)1e9+7;
51 const int N=(int)1e6+10;
52
53 int er[17]={1,2,4,8,16,32,64,128,256,512,1024,2048,4096,8192,16384,32768,65536};
54 int a[N],b[N];
55
56 template<class _Ty = void>
57 struct more:public binary_function<_Ty, _Ty, bool>
58 {
59 bool operator()(const _Ty& _Left, const _Ty& _Right) const
60 {
61 return (_Left > _Right);
62 }
63 };
64
65 ll get(int x,int n,int k)
66 {
67 ll sum=0;
68 int rk=0;
69 int r=0;
70 for(int i=1;i<=n;++i)
71 {
72 if(i!=1)
73 {
74 if(a[i-1]>=x)
75 rk--;
76 }
77 while(rk<k&&r+1<=n)
78 {
79 r++;
80 if(a[r]>=x)rk++;
81 }
82 if(rk>=k)sum+=n-r+1;
83 }
84 return sum;
85 }
86
87 void solve()
88 {
89 int n,k;
90 ll m;
91 sc("%d%d%lld",&n,&k,&m);
92 for(int i=1;i<=n;++i)
93 sc("%d",&a[i]),b[i]=a[i];
94 sort(b+1,b+1+n);
95 int temp=0;
96 for(int i=16;i>=0;--i)
97 {
98 if(temp+er[i]<=n&&get(b[temp+er[i]],n,k)>=m)
99 temp+=er[i];
100 }
101 pr("%d\n",b[temp]);
102 }
103
104 int main()
105 {
106 int T;
107 sc("%d",&T);
108 while(T--)solve();
109 return 0;
110 }
111
112 /**************************************************************************************/
113
114 int maxx(int a,int b)
115 {
116 return a>b?a:b;
117 }
118
119 void swapp(int &a,int &b)
120 {
121 a^=b^=a^=b;
122 }
123
124 int lowbit(int n)
125 {
126 return n&(-n);
127 }
128
129 int Del_bit_1(int n)
130 {
131 return n&(n-1);
132 }
133
134 int abss(int a)
135 {
136 return a>0?a:-a;
137 }
138
139 double fabss(double a)
140 {
141 return a>0?a:-a;
142 }
143
144 int minn(int a,int b)
145 {
146 return a<b?a:b;
147 }
标签：二分,__,return,int,double,void,尺取,include 来源： https://www.cnblogs.com/--HPY-7m/p/11706937.html