fun main(){
    val n = readLine()!!.toInt()
    val s = readLine()!!
    val a = mutableListOf<Long>()
    a += readLine()!!.split(" ").map{it.toLong()}
    for(i in 0..n-1){
        if(s[i] == 'R')   a[i] = a[i] * -1L
        if(i > 0)   a[i] += a[i-1]
    }
    var answer = Math.abs(a[0])
    var befmin = Math.min(0, a[0])
    var befmax = Math.max(0, a[0])
    for(i in 1..n-1){
        answer = Math.max(answer, Math.max(Math.abs(befmin-a[i]), Math.abs(befmax-a[i])))
        befmin = Math.min(befmin, a[i])
        befmax = Math.max(befmax, a[i])
    }
    println(answer)
}