求助各位大牛 代码如下：

#include <bits/stdc++.h>
using namespace std;
const int MAXN = 1e6 + 10;
int x[MAXN];

inline int read() {
	int x = 0, f = 1;
	char ch = getchar();
	for (; (ch >= '0' && ch <= '9') || ch == '-'; ch = getchar())
		ch == '-' ? f = -1 : x = x * 10 + ch - '0';
	return x * f;
}

int main(){
int a=read();
int b=read();
for(int i=1;i<=a;i++){
  x[i]=read();
}
while(b--){
  int t=read();
  int ans=lower_bound(x+1,x+a+1,t)-x;
  if(t!=x[ans]) printf("-1 ");
  else printf("%d ",ans);
}
}