hdu 5806 NanoApe Loves Sequence Ⅱ (尺取法)

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NanoApe Loves Sequence Ⅱ


Time Limit: 4000/2000 MS (Java/Others)    Memory Limit: 262144/131072 K (Java/Others)

Total Submission(s): 500    Accepted Submission(s): 242

Problem Description
NanoApe, the Retired Dog, has returned back to prepare for for the National Higher Education Entrance Examination!

In math class, NanoApe picked up sequences once again. He wrote down a sequence with





n



numbers and a number





m



on the paper.

Now he wants to know the number of continous subsequences of the sequence in such a manner that the





k



-th largest number in the subsequence is no less than





m



.

Note : The length of the subsequence must be no less than





k



.









Input
The first line of the input contains an integer





T



, denoting the number of test cases.

In each test case, the first line of the input contains three integers





n

,

m

,

k







.

The second line of the input contains





n



integers






A

1

,


A

2

,

.

.

.

,


A

n

















, denoting the elements of the sequence.






1



T



10

,


2



n



200000

,


1



k



n



/

2

,


1



m

,


A

i




10

9















































Output
For each test case, print a line with one integer, denoting the answer.

Sample Input
1
7 4 2
4 2 7 7 6 5 1

Sample Output
18
#include <cstdio>
#include <cstring>
#include <algorithm>
#include <map>
#include <set>
using namespace std;
#define ll long long
int s[200010];
int main() {
    int t;
    scanf("%d", &t);
    while(t--) {
        ll n,k,t;
        scanf("%I64d %I64d %I64d", &n, &t, &k);
        s[0] = 0;
        for(int i = 1; i <= n; i++) {
            s[i] = s[i-1];
            int tmp;
            scanf("%d", &tmp);
            if(tmp >= t) s[i]++;
        }
        ll beg = 0, end = k, ans = 0;
        while(end <= n) {
            while(s[end] - s[beg] >= k)beg++;
            ans += beg;
            end++; 
        }
        printf("%I64d\n", ans);
    }
    return 0;
}

转载于:https://www.cnblogs.com/lonewanderer/p/5745707.html