UVA 11991 - c++编程基础

[cpp]
#include
#include
#include
#include
using namespace std;

map > a;

int main(){
int n, m, x, y; www.2cto.com
while(scanf("%d%d", &n, &m)) {
a.clear();
for(int i = 0; i < n; i++) {
scanf("%d", &x);

if(!a.count(x)) {
a[x] = vector();
}
a[x].push_back(i+1);
}
while(m--) {
scanf("%d%d", &x, &y);
if(!a.count(y) || a[y].size() < x){
printf("0\n");
}
else{
printf("%d\n", a[y][x-1]);
}
}
}
}