import std.conv, std.functional, std.range, std.stdio, std.string;
import std.algorithm, std.array, std.bigint, std.bitmanip, std.complex, std.container, std.math, std.numeric, std.regex, std.typecons;
import core.bitop;

class EOFException : Throwable { this() { super("EOF"); } }
string[] tokens;
string readToken() { for (; tokens.empty; ) { if (stdin.eof) { throw new EOFException; } tokens = readln.split; } auto token = tokens.front; tokens.popFront; return token; }
int readInt() { return readToken.to!int; }
long readLong() { return readToken.to!long; }
real readReal() { return readToken.to!real; }

bool chmin(T)(ref T t, in T f) { if (t > f) { t = f; return true; } else { return false; } }
bool chmax(T)(ref T t, in T f) { if (t < f) { t = f; return true; } else { return false; } }

int binarySearch(alias pred, T)(in T[] as) { int lo = -1, hi = cast(int)(as.length); for (; lo + 1 < hi; ) { const mid = (lo + hi) >> 1; (unaryFun!pred(as[mid]) ? hi : lo) = mid; } return hi; }
int lowerBound(T)(in T[] as, T val) { return as.binarySearch!(a => (a >= val)); }
int upperBound(T)(in T[] as, T val) { return as.binarySearch!(a => (a > val)); }




void main() {
  try {
    for (; ; ) {
      const S = readToken();
      const N = cast(int)(S.length);
      
      int[] xs;
      foreach (i; 0 .. N + 1) {
        if ((i == 0 || S[i - 1] == '>') && (i == N || S[i] == '<')) {
          xs ~= i;
        }
      }
      const xsLen = cast(int)(xs.length);
      debug {
        writeln("xs = ", xs);
      }
      
      auto ans = new long[N + 1];
      foreach (i; 0 .. xs[0] + 1) {
        ans[i] = xs[0] - i;
      }
      foreach (i; xs[xsLen - 1] .. N + 1) {
        ans[i] = i - xs[xsLen - 1];
      }
      
      foreach (j; 0 .. xsLen - 1) {
        const a = xs[j];
        const b = xs[j + 1];
        int c;
        for (c = a; c < b && S[c] == '<'; ++c) {}
        debug {
          writeln(a, " ", c, " ", b);
        }
        foreach (i; a .. c) {
          ans[i] = i - a;
        }
        ans[c] = max(c - a, b - c);
        foreach (i; c + 1 .. b) {
          ans[i] = b - i;
        }
      }
      
      debug {
        writeln(ans);
      }
      writeln(ans.sum);
    }
  } catch (EOFException e) {
  }
}
