Uva 11991 - Easy Problem from Rujia Liu?（map 查找）

#include<cstdio>
#include<vector>
#include<map>
using namespace std;

map<int, vector<int> > m;
int main()
{
int n, t, temp, i, k, l;
while(scanf("%d%d", &n, &t) == 2)
{
m.clear();
for(i = 0; i < n; i++)
{
scanf("%d", &temp);
if (! m.count(temp))
m [temp] = vector<int>();
m [temp].push_back(i + 1);
}
while (t--)
{
scanf("%d%d", &k, &l);
if(m[l].empty() || k > m[l].size())
printf("0\n");
else
printf("%d\n", m[l][k-1]);
}
}
return 0;
}