The kth great number（set）

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The kth great number

Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65768/65768 K (Java/Others)
Total Submission(s): 9407    Accepted Submission(s): 3752

Problem DescriptionXiao Ming and Xiao Bao are playing a simple Numbers game. In a round Xiao Ming can choose to write down a number, or ask Xiao Bao what the kth great number is. Because the number written by Xiao Ming is too much, Xiao Bao is feeling giddy. Now, try to help Xiao Bao. 

 

InputThere are several test cases. For each test case, the first line of input contains two positive integer n, k. Then n lines follow. If Xiao Ming choose to write down a number, there will be an " I" followed by a number that Xiao Ming will write down. If Xiao Ming choose to ask Xiao Bao, there will be a "Q", then you need to output the kth great number.  

 

OutputThe output consists of one integer representing the largest number of islands that all lie on one line.  

 

Sample Input8 3I 1I 2I 3QI 5QI 4Q 

 

Sample Output123 HintXiao Ming won‘t ask Xiao Bao the kth great number when the number of the written number is smaller than k. (1=<k<=n<=1000000). 題解：只需要維護前K大數就好了；代碼：

#include<stdio.h>#include<queue>#include<string.h>#include<algorithm>#include<iostream>#include<queue>#include<set>#include<vector>#define INF 0x3f3f3f3fusing namespace std;struct Node{    int v;    friend bool operator < (Node a, Node b){        return a.v > b.v;    }};multiset<Node>st;multiset<Node>::iterator iter;int main(){    int n, k;    char s[2];    Node d;    while(~scanf("%d%d", &n, &k)){        st.clear();        int ans = 0x3f3f3f3f;        for(int i = 0; i < n; i++){            scanf("%s", s);            if(s[0] == ‘I‘){                scanf("%d", &d.v);                st.insert(d);                iter = st.end();                iter--;                if(st.size() > k)                    st.erase(iter);            }            else{                iter = st.end();                iter--;                printf("%d\n", *iter);            }        }    }    return 0;}

 還可以用vector;

代碼：

#include<iostream>#include<cstring>#include<cstdio>#include<vector>#include<algorithm>using namespace std;vector<int>vec;vector<int>::iterator iter;int main(){    int n, k;    char s[2];    while(~scanf("%d%d", &n, &k)){        vec.clear();        for(int i = 0; i < n; i++){            scanf("%s", s);            int v;            if(s[0] == ‘I‘){                scanf("%d", &v);                iter = lower_bound(vec.begin(), vec.end(), v);                vec.insert(iter, v);            }            else{                printf("%d\n", vec[vec.size() - k]);            }        }    }    return 0;}

 

The kth great number（set）