use std::collections::{BTreeSet, HashMap}; const MOD: usize = 1e9 as usize + 7; #[derive(Debug, Clone)] struct SegmentTree { n: usize, orgn: usize, unit: T, mem: Vec, operator: F } impl SegmentTree where T: std::fmt::Debug + Copy, F: Fn(T, T) -> T { fn new(n: usize, unit: T, operator: F) -> Self { let mut size = 1usize; while size < n { size *= 2; } Self { n: size, orgn: n, unit: unit, mem: vec![unit; size*2-1], operator: operator, } } fn find_closed(&self, l: usize, r: usize) -> T { self.find(l, r+1) } fn find(&self, l: usize, r: usize) -> T { self._find(l, r, 0, 0, self.n) } fn set(&mut self, pos: usize, val: T) { let mut pos = pos + self.n - 1; self.mem[pos] = val; while pos > 0 { pos = self._parent(pos); self.mem[pos] = (self.operator)(self.mem[self._left(pos)], self.mem[self._right(pos)]); } } fn get(&mut self, pos: usize) -> T { self.mem[pos + self.n - 1] } fn _find(&self, a: usize, b: usize, nodenum: usize, l: usize, r: usize) -> T { if r <= a || b <= l { return self.unit; } else if a <= l && r <= b { return self.mem[nodenum]; } let left = self._find(a, b, self._left(nodenum), l, (l+r)/2); let right = self._find(a, b, self._right(nodenum), (l+r)/2, r); (self.operator)(left, right) } fn _left(&self, k: usize) -> usize { 2*k+1 } fn _right(&self, k: usize) -> usize { 2*k+2 } fn _parent(&self, k: usize) -> usize { (k-1)/2 } } fn main() { let mut nk = String::new(); std::io::stdin().read_line(&mut nk).ok(); let nk: Vec = nk.trim().split_whitespace().map(|s| s.parse().unwrap()).collect(); let n = nk[0]; let k = nk[1]; let mut a = String::new(); std::io::stdin().read_line(&mut a).ok(); let a: Vec = a.trim().split_whitespace().map(|s| s.parse().unwrap()).collect(); let mut s = String::new(); std::io::stdin().read_line(&mut s).ok(); let s = s.trim().chars().collect::>(); let aset = a.iter().copied().collect::>(); let mut amap = HashMap::new(); for (i, &v) in aset.iter().enumerate() { amap.insert(v, i); } let mut segtrees = vec![SegmentTree::new(aset.len(), 0usize, |x, y| x + y); k+1]; for i in 0..n { let aidx = *amap.get(&a[i]).unwrap(); let cur = segtrees[1].get(aidx); segtrees[0].set(aidx, cur+1); for j in 0..k { let left = if s[j] == '>' { aidx+1 } else { 0 }; let right = if s[j] == '>' { aset.len() } else { aidx }; let addval = segtrees[j].find(left, right); let current = segtrees[j+1].get(aidx); segtrees[j+1].set(aidx, (current + addval) % MOD); } } println!("{}", segtrees[k].find(0, aset.len()) % MOD); }