题解，首AC

#include<bits/stdc++.h>
using namespace std;
inline int read() {
	int x = 0, f = 1;
	char ch = getchar();
	while (ch < '0' || ch > '9') {
		if (ch == '-')f = -1;
		ch = getchar();
	}
	while (ch >= '0' && ch <= '9') {
		x = (x << 1) + (x << 3) + (ch ^ 48);
		ch = getchar();
	}
	return x * f;
}//快读YYDS 
int main() {
	int n = read(), m = read(), a[n + 1];
	for (int i = 1; i <= n; ++i)a[i] = read();
	while (m--) {
		int tmp = read();
		int ans = lower_bound(a + 1, a + n + 1, tmp) - a;
		a[ans] == tmp&&ans <= n/*记得特判*/ ? cout << ans << " " : cout << -1 << " ";
	}
	return 0;
}