package main

import (
    "fmt"
)


func pop(a []int, x int) ([]int, int) {
    var r int
    r = a[x]
    if x == len(a)-1 {
        a = a[:x]
    } else {
        a = append(a[:x], a[x+1:]...)
    }
    return a, r
}

func main() {
    var N, M int
    fmt.Scan(&N, &M)
    s := make([]int, N)
    for i := 0; i<N; i++ {
        s[i] = i
    }
    //    fmt.Println(s)
    var a int
    for i := 0; i<M; i++ {
        fmt.Scan(&a)
        a -= 1
        s, a = pop(s, a)
        tmp_slice := []int{a}
        //        fmt.Println(s)
        //        fmt.Println(a)
        s = append(tmp_slice, s[:]...)
        //        fmt.Println(s)
    }
    fmt.Println(s[0]+1)
//    print(s[0]+1)
}