奖励关

循环遍历，找就完了

参考代码（python）

from sys import stdin,setrecursionlimit
from math import inf,ceil,sqrt
from collections import Counter,deque

n,x=[int(_) for _ in stdin.readline().split()]
a=[int(_) for _ in stdin.readline().split()]
for i in range(n):
    if a[i]==x:
        print(i+1)
        exit()
print(-1)