BNU20409 UVA11991

来源:互联网 发布:区域经济考研知乎 编辑:程序博客网 时间:2024/04/30 17:38
Time Limit: 1000ms
Memory Limit: 131072KB
This problem will be judged on UVA. Original ID: 11991
64-bit integer IO format: %lld      Java class name: Main
Prev 
Submit Status Statistics Discuss
 Next
Type: 
None
     

    [PDF Link]

    Problem E

    Easy Problem from Rujia Liu?

    Though Rujia Liu usually sets hard problems for contests (for example, regional contests like Xi'an 2006, Beijing 2007 and Wuhan 2009, or UVa OJ contests like Rujia Liu's Presents 1 and 2), he occasionally sets easy problem (for example, 'the Coco-Cola Store' in UVa OJ), to encourage more people to solve his problems :D

    Given an array, your task is to find the k-th occurrence (from left to right) of an integer v. To make the problem more difficult (and interesting!), you'll have to answer m such queries.

    Input

    There are several test cases. The first line of each test case contains two integers n, m(1<=n,m<=100,000), the number of elements in the array, and the number of queries. The next line contains n positive integers not larger than 1,000,000. Each of the following m lines contains two integer k and v (1<=k<=n, 1<=v<=1,000,000). The input is terminated by end-of-file (EOF). The size of input file does not exceed 5MB.

    Output

    For each query, print the 1-based location of the occurrence. If there is no such element, output 0 instead.

    Sample Input

    8 41 3 2 2 4 3 2 11 32 43 24 2

    Output for the Sample Input

    2070

    https://www.bnuoj.com/v3/problem_show.php?pid=20409

    题意给出一个包含n个整数的数组,你需要回答若干询问.每次询问两个整数k和v,输出从左到右第k个V的下标(数组下标从左到右1-n)

    限制了内存好像没什么方法了 只有map和vector相套了

    #include<stdio.h>#include<map>#include<vector>using namespace std;int main(){    map<int,vector<int> > a;//两个> >要写开    int i,x,n,m,k;    while(scanf("%d%d",&n,&m)!=EOF)    {        a.clear();        for(i=0; i<n; i++)        {            scanf("%d",&x);            if(!a.count(x))              a[x]=vector<int>();//注意 创建一个属于它的空容器            a[x].push_back(i+1);        }        while(m--)        {            scanf("%d%d",&k,&x);            if(a[x].size()<k)            {                printf("0\n");                continue;            }            printf("%d\n",a[x][k-1]);        }    }    return 0;}



    0 0