lowerbound

/*
 Author: 曹北健
 Result: AC    Submission_id: 3474027
 Created at: Wed May 12 2021 16:24:46 GMT+0800 (China Standard Time)
 Problem_id: 4335    Time: 333    Memory: 7468
*/
#include <stdio.h>
#include <stdlib.h>
#include <ctype.h>
#include <math.h>
#include <string.h>
#include <assert.h>
#pragma warning(disable:4996)
#define MAX(a,b) (((a)>(b))?(a):(b))
#define MIN(a,b) (((a)<(b))?(a):(b))
typedef long long LL;
typedef unsigned long long ULL;
int compare(const void *p,const void *q){
    int a = *(int *)p,b = *(int *)q;
    if(a < b)return -1;
    else if(a > b)return 1;
    else return 0;
}
void *lowerbound(void *base,void *key,size_t count,size_t itemsize,int(*compare)(const void *,const void *)){
    assert(base && compare);
    size_t lo = 0,hi = count - 1,mid = 0;
    if(compare(key,(char *)base + hi * itemsize) > 0){
        return (char *)base + count * itemsize;
    }
    char *pmid = 0;
    while(lo < hi){
        mid = (lo + hi) >> 1;
        pmid = ((char *)base) + mid * itemsize;
        if(compare(pmid,key) < 0){
            lo = mid + 1;
        }
        else{
            hi = mid;
        }
    }
    return (char *)base + lo * itemsize;
}
void *upperbound(void *base,void *key,size_t count,size_t itemsize,int(*compare)(const void *,const void *)){
    assert(base && compare);
    size_t lo = 0,hi = count - 1,mid;
    if(compare(key,(char *)base + hi * itemsize) >= 0){
        return (char *)base + count * itemsize;
    }
    char *pmid = 0;
    while(lo < hi){
        mid = (lo + hi) >> 1;
        char *pmid = ((char *)base) + mid * itemsize;
        if(compare(pmid,key) <= 0){
            lo = mid + 1;
        }
        else{
            hi = mid;
        }
    }
    return (char *)base + lo * itemsize;
}
int a[1919810] = {0};
int main(){
#ifdef _DEBUG
    freopen("input.txt","r",stdin);
#ifdef OFILE
    freopen("test.txt","w",stdout);
#endif
#endif
    int i,n,m,t;
    scanf("%d%d",&n,&m);
    for(i = 0;i < n;i++){
        scanf("%d",a + i);
    }
    while(m--){
        scanf("%d",&t);
        int *p = (int *)lowerbound(a,&t,n,sizeof(int),compare);
        //printf("%d ",*p);
        if(*p != t){
            puts("-1");
        }
        else{
            printf("%d\n",p - a + 1);
        }
    }
#ifdef _DEBUG
    freopen("CON","r",stdin);
#ifdef OFILE
    freopen("CON","w",stdout);
#endif
    system("pause");
#endif
    return 0;
    }