免费题解随意复制粘贴，后果概不负责

#include <bits/stdc++.h>
using namespace std;
int n, m;
int a[100005] = {-1};
int ans[100005];

void func(int x){
int low = lower_bound(a + 1, a + n + 1, x) - a;
int high = upper_bound(a + 1, a + n + 1, x) - a - 1;
int next = upper_bound(a + 1, a + n + 1, x) - a;
if(next > n){
next = -1;
}
if(a[low] != x){
low = -1;
}
if(a[high] != x){
high = -1;
}
cout << low << ' ' << high << ' ' << next << endl;
return;
}

int main(){
cin >> n;
for(int i = 1; i <= n; i++){
cin >> a[i];
}
cin >> m;
int temp;
for(int i = 1; i <= m; i++){
cin >> ans[i];
}
for(int i = 1; i <= m; i++){
func(ans[i]);
}
}