Problem: Valera has a strip infinite in both directions and consisting of cells. The cells are numbered by integers. The cell number 0 has a robot.

The robot has instructions — the sequence of moves that he must perform. In one move, the robot moves one cell to the left or one cell to the right, according to instructions. Before the robot starts moving, Valera puts obstacles in some cells of the strip, excluding cell number 0. If the robot should go into the cell with an obstacle according the instructions, it will skip this move.

Also Valera indicates the finish cell in which the robot has to be after completing the entire instructions. The finishing cell should be different from the starting one. It is believed that the robot completed the instructions successfully, if during the process of moving he visited the finish cell exactly once — at its last move. Moreover, the latter move cannot be skipped.

Let's assume that k is the minimum number of obstacles that Valera must put to make the robot able to complete the entire sequence of instructions successfully and end up in some finishing cell. You need to calculate in how many ways Valera can choose k obstacles and the finishing cell so that the robot is able to complete the instructions successfully.

Input

The first line contains a sequence of characters without spaces s1s2... sn (1 ≤ n ≤ 106), consisting only of letters "L" and "R". If character si equals "L", then the robot on the i-th move must try to move one cell to the left. If the si-th character equals "R", then the robot on the i-th move must try to move one cell to the right.

Output

Print a single integer — the required number of ways. It's guaranteed that this number fits into 64-bit signed integer type.

Examples

Input

RR


Output

1


Input

RRL


Output

1

Note

In the first sample Valera mustn't add any obstacles and his finishing cell must be cell 2.

In the second sample, Valera must add an obstacle in cell number 1, and his finishing cell must be cell number  - 1. In this case robot skips the first two moves and on the third move he goes straight from the starting cell to the finishing one. But if Valera doesn't add any obstacles, or adds an obstacle to another cell, then the robot visits the finishing cell more than once.

Solution (in CPP):

Solution:
#include <bits/stdc++.h>
#pragma comment(linker, "/STACK:36777216")
using namespace std;
template <class T>
inline T &RD(T &);
template <class T>
inline void OT(const T &);
inline long long RD() {
  long long x;
  return RD(x);
}
inline double &RF(double &);
inline double RF() {
  double x;
  return RF(x);
}
inline char *RS(char *s);
inline char &RC(char &c);
inline char RC();
inline char &RC(char &c) {
  scanf(" %c", &c);
  return c;
}
inline char RC() {
  char c;
  return RC(c);
}
template <class T>
inline T &RDD(T &);
inline long long RDD() {
  long long x;
  return RDD(x);
}
template <class T0, class T1>
inline T0 &RD(T0 &x0, T1 &x1) {
  RD(x0), RD(x1);
  return x0;
}
template <class T0, class T1, class T2>
inline T0 &RD(T0 &x0, T1 &x1, T2 &x2) {
  RD(x0), RD(x1), RD(x2);
  return x0;
}
template <class T0, class T1, class T2, class T3>
inline T0 &RD(T0 &x0, T1 &x1, T2 &x2, T3 &x3) {
  RD(x0), RD(x1), RD(x2), RD(x3);
  return x0;
}
template <class T0, class T1, class T2, class T3, class T4>
inline T0 &RD(T0 &x0, T1 &x1, T2 &x2, T3 &x3, T4 &x4) {
  RD(x0), RD(x1), RD(x2), RD(x3), RD(x4);
  return x0;
}
template <class T0, class T1, class T2, class T3, class T4, class T5>
inline T0 &RD(T0 &x0, T1 &x1, T2 &x2, T3 &x3, T4 &x4, T5 &x5) {
  RD(x0), RD(x1), RD(x2), RD(x3), RD(x4), RD(x5);
  return x0;
}
template <class T0, class T1, class T2, class T3, class T4, class T5, class T6>
inline T0 &RD(T0 &x0, T1 &x1, T2 &x2, T3 &x3, T4 &x4, T5 &x5, T6 &x6) {
  RD(x0), RD(x1), RD(x2), RD(x3), RD(x4), RD(x5), RD(x6);
  return x0;
}
template <class T0, class T1>
inline void OT(const T0 &x0, const T1 &x1) {
  OT(x0), OT(x1);
}
template <class T0, class T1, class T2>
inline void OT(const T0 &x0, const T1 &x1, const T2 &x2) {
  OT(x0), OT(x1), OT(x2);
}
template <class T0, class T1, class T2, class T3>
inline void OT(const T0 &x0, const T1 &x1, const T2 &x2, const T3 &x3) {
  OT(x0), OT(x1), OT(x2), OT(x3);
}
template <class T0, class T1, class T2, class T3, class T4>
inline void OT(const T0 &x0, const T1 &x1, const T2 &x2, const T3 &x3,
               const T4 &x4) {
  OT(x0), OT(x1), OT(x2), OT(x3), OT(x4);
}
template <class T0, class T1, class T2, class T3, class T4, class T5>
inline void OT(const T0 &x0, const T1 &x1, const T2 &x2, const T3 &x3,
               const T4 &x4, const T5 &x5) {
  OT(x0), OT(x1), OT(x2), OT(x3), OT(x4), OT(x5);
}
template <class T0, class T1, class T2, class T3, class T4, class T5, class T6>
inline void OT(const T0 &x0, const T1 &x1, const T2 &x2, const T3 &x3,
               const T4 &x4, const T5 &x5, const T6 &x6) {
  OT(x0), OT(x1), OT(x2), OT(x3), OT(x4), OT(x5), OT(x6);
}
inline char &RC(char &a, char &b) {
  RC(a), RC(b);
  return a;
}
inline char &RC(char &a, char &b, char &c) {
  RC(a), RC(b), RC(c);
  return a;
}
inline char &RC(char &a, char &b, char &c, char &d) {
  RC(a), RC(b), RC(c), RC(d);
  return a;
}
inline char &RC(char &a, char &b, char &c, char &d, char &e) {
  RC(a), RC(b), RC(c), RC(d), RC(e);
  return a;
}
inline char &RC(char &a, char &b, char &c, char &d, char &e, char &f) {
  RC(a), RC(b), RC(c), RC(d), RC(e), RC(f);
  return a;
}
inline char &RC(char &a, char &b, char &c, char &d, char &e, char &f, char &g) {
  RC(a), RC(b), RC(c), RC(d), RC(e), RC(f), RC(g);
  return a;
}
inline double &RF(double &a, double &b) {
  RF(a), RF(b);
  return a;
}
inline double &RF(double &a, double &b, double &c) {
  RF(a), RF(b), RF(c);
  return a;
}
inline double &RF(double &a, double &b, double &c, double &d) {
  RF(a), RF(b), RF(c), RF(d);
  return a;
}
inline double &RF(double &a, double &b, double &c, double &d, double &e) {
  RF(a), RF(b), RF(c), RF(d), RF(e);
  return a;
}
inline double &RF(double &a, double &b, double &c, double &d, double &e,
                  double &f) {
  RF(a), RF(b), RF(c), RF(d), RF(e), RF(f);
  return a;
}
inline double &RF(double &a, double &b, double &c, double &d, double &e,
                  double &f, double &g) {
  RF(a), RF(b), RF(c), RF(d), RF(e), RF(f), RF(g);
  return a;
}
inline void RS(char *s1, char *s2) { RS(s1), RS(s2); }
inline void RS(char *s1, char *s2, char *s3) { RS(s1), RS(s2), RS(s3); }
template <class T0, class T1>
inline void RDD(T0 &a, T1 &b) {
  RDD(a), RDD(b);
}
template <class T0, class T1, class T2>
inline void RDD(T0 &a, T1 &b, T2 &c) {
  RDD(a), RDD(b), RDD(c);
}
template <class T>
inline void RST(T &A) {
  memset(A, 0, sizeof(A));
}
template <class T>
inline void FLC(T &A, int x) {
  memset(A, x, sizeof(A));
}
template <class T>
inline void CLR(T &A) {
  A.clear();
}
template <class T0, class T1>
inline void RST(T0 &A0, T1 &A1) {
  RST(A0), RST(A1);
}
template <class T0, class T1, class T2>
inline void RST(T0 &A0, T1 &A1, T2 &A2) {
  RST(A0), RST(A1), RST(A2);
}
template <class T0, class T1, class T2, class T3>
inline void RST(T0 &A0, T1 &A1, T2 &A2, T3 &A3) {
  RST(A0), RST(A1), RST(A2), RST(A3);
}
template <class T0, class T1, class T2, class T3, class T4>
inline void RST(T0 &A0, T1 &A1, T2 &A2, T3 &A3, T4 &A4) {
  RST(A0), RST(A1), RST(A2), RST(A3), RST(A4);
}
template <class T0, class T1, class T2, class T3, class T4, class T5>
inline void RST(T0 &A0, T1 &A1, T2 &A2, T3 &A3, T4 &A4, T5 &A5) {
  RST(A0), RST(A1), RST(A2), RST(A3), RST(A4), RST(A5);
}
template <class T0, class T1, class T2, class T3, class T4, class T5, class T6>
inline void RST(T0 &A0, T1 &A1, T2 &A2, T3 &A3, T4 &A4, T5 &A5, T6 &A6) {
  RST(A0), RST(A1), RST(A2), RST(A3), RST(A4), RST(A5), RST(A6);
}
template <class T0, class T1>
inline void FLC(T0 &A0, T1 &A1, int x) {
  FLC(A0, x), FLC(A1, x);
}
template <class T0, class T1, class T2>
inline void FLC(T0 &A0, T1 &A1, T2 &A2, int x) {
  FLC(A0, x), FLC(A1, x), FLC(A2, x);
}
template <class T0, class T1, class T2, class T3>
inline void FLC(T0 &A0, T1 &A1, T2 &A2, T3 &A3, int x) {
  FLC(A0, x), FLC(A1, x), FLC(A2, x), FLC(A3, x);
}
template <class T0, class T1, class T2, class T3, class T4>
inline void FLC(T0 &A0, T1 &A1, T2 &A2, T3 &A3, T4 &A4, int x) {
  FLC(A0, x), FLC(A1, x), FLC(A2, x), FLC(A3, x), FLC(A4, x);
}
template <class T0, class T1, class T2, class T3, class T4, class T5>
inline void FLC(T0 &A0, T1 &A1, T2 &A2, T3 &A3, T4 &A4, T5 &A5, int x) {
  FLC(A0, x), FLC(A1, x), FLC(A2, x), FLC(A3, x), FLC(A4, x), FLC(A5, x);
}
template <class T0, class T1, class T2, class T3, class T4, class T5, class T6>
inline void FLC(T0 &A0, T1 &A1, T2 &A2, T3 &A3, T4 &A4, T5 &A5, T6 &A6, int x) {
  FLC(A0, x), FLC(A1, x), FLC(A2, x), FLC(A3, x), FLC(A4, x), FLC(A5, x),
      FLC(A6, x);
}
template <class T>
inline void CLR(priority_queue<T, vector<T>, less<T> > &Q) {
  while (!Q.empty()) Q.pop();
}
template <class T>
inline void CLR(priority_queue<T, vector<T>, greater<T> > &Q) {
  while (!Q.empty()) Q.pop();
}
template <class T>
inline void CLR(stack<T> &S) {
  while (!S.empty()) S.pop();
}
template <class T0, class T1>
inline void CLR(T0 &A0, T1 &A1) {
  CLR(A0), CLR(A1);
}
template <class T0, class T1, class T2>
inline void CLR(T0 &A0, T1 &A1, T2 &A2) {
  CLR(A0), CLR(A1), CLR(A2);
}
template <class T0, class T1, class T2, class T3>
inline void CLR(T0 &A0, T1 &A1, T2 &A2, T3 &A3) {
  CLR(A0), CLR(A1), CLR(A2), CLR(A3);
}
template <class T0, class T1, class T2, class T3, class T4>
inline void CLR(T0 &A0, T1 &A1, T2 &A2, T3 &A3, T4 &A4) {
  CLR(A0), CLR(A1), CLR(A2), CLR(A3), CLR(A4);
}
template <class T0, class T1, class T2, class T3, class T4, class T5>
inline void CLR(T0 &A0, T1 &A1, T2 &A2, T3 &A3, T4 &A4, T5 &A5) {
  CLR(A0), CLR(A1), CLR(A2), CLR(A3), CLR(A4), CLR(A5);
}
template <class T0, class T1, class T2, class T3, class T4, class T5, class T6>
inline void CLR(T0 &A0, T1 &A1, T2 &A2, T3 &A3, T4 &A4, T5 &A5, T6 &A6) {
  CLR(A0), CLR(A1), CLR(A2), CLR(A3), CLR(A4), CLR(A5), CLR(A6);
}
template <class T>
inline void CLR(T &A, int n) {
  for (int i = 0; i < n; ++i) CLR(A[i]);
}
template <class T>
inline bool EPT(T &a) {
  return a.empty();
}
template <class T>
inline T &SRT(T &A) {
  sort(A.begin(), A.end());
  return A;
}
template <class T, class C>
inline T &SRT(T &A, C B) {
  sort(A.begin(), A.end(), B);
  return A;
}
template <class T>
inline T &RVS(T &A) {
  reverse(A.begin(), A.end());
  return A;
}
template <class T>
inline T &UNQQ(T &A) {
  A.resize(unique(A.begin(), A.end()) - A.begin());
  return A;
}
template <class T>
inline T &UNQ(T &A) {
  SRT(A);
  return UNQQ(A);
}
const int MOD = int(1e9) + 7;
const int INF = 0x3f3f3f3f;
const long long INFF = 0x3f3f3f3f3f3f3f3fLL;
const double EPS = 1e-9;
const double OO = 1e20;
const double PI = acos(-1.0);
const int dx[] = {-1, 0, 1, 0};
const int dy[] = {0, 1, 0, -1};
template <class T>
inline T &checkMin(T &a, const T b) {
  if (b < a) a = b;
  return a;
}
template <class T>
inline T &checkMax(T &a, const T b) {
  if (a < b) a = b;
  return a;
}
template <class T>
inline T &checkMin(T &a, T &b, const T x) {
  checkMin(a, x), checkMin(b, x);
  return a;
}
template <class T>
inline T &checkMax(T &a, T &b, const T x) {
  checkMax(a, x), checkMax(b, x);
  return a;
}
template <class T, class C>
inline T &checkMin(T &a, const T b, C c) {
  if (c(b, a)) a = b;
  return a;
}
template <class T, class C>
inline T &checkMax(T &a, const T b, C c) {
  if (c(a, b)) a = b;
  return a;
}
template <class T>
inline T min(T a, T b, T c) {
  return min(min(a, b), c);
}
template <class T>
inline T max(T a, T b, T c) {
  return max(max(a, b), c);
}
template <class T>
inline T min(T a, T b, T c, T d) {
  return min(min(a, b), min(c, d));
}
template <class T>
inline T max(T a, T b, T c, T d) {
  return max(max(a, b), max(c, d));
}
template <class T>
inline T min(T a, T b, T c, T d, T e) {
  return min(min(min(a, b), min(c, d)), e);
}
template <class T>
inline T max(T a, T b, T c, T d, T e) {
  return max(max(max(a, b), max(c, d)), e);
}
template <class T>
inline T sqr(T a) {
  return a * a;
}
template <class T>
inline T cub(T a) {
  return a * a * a;
}
template <class T>
inline T ceil(T x, T y) {
  return (x - 1) / y + 1;
}
template <class T>
T abs(T x) {
  return x > 0 ? x : -x;
}
inline int sgn(double x) { return x < -EPS ? -1 : x > EPS; }
inline int sgn(double x, double y) { return sgn(x - y); }
inline double cos(double a, double b, double c) {
  return (sqr(a) + sqr(b) - sqr(c)) / (2 * a * b);
}
inline double cot(double x) { return 1. / tan(x); };
inline double sec(double x) { return 1. / cos(x); };
inline double csc(double x) { return 1. / sin(x); };
namespace BO {
inline bool _1(int x, int i) { return bool(x & 1 << i); }
inline bool _1(long long x, int i) { return bool(x & 1LL << i); }
inline long long _1(int i) { return 1LL << i; }
inline long long _U(int i) { return _1(i) - 1; };
inline int reverse_bits(int x) {
  x = ((x >> 1) & 0x55555555) | ((x << 1) & 0xaaaaaaaa);
  x = ((x >> 2) & 0x33333333) | ((x << 2) & 0xcccccccc);
  x = ((x >> 4) & 0x0f0f0f0f) | ((x << 4) & 0xf0f0f0f0);
  x = ((x >> 8) & 0x00ff00ff) | ((x << 8) & 0xff00ff00);
  x = ((x >> 16) & 0x0000ffff) | ((x << 16) & 0xffff0000);
  return x;
}
inline long long reverse_bits(long long x) {
  x = ((x >> 1) & 0x5555555555555555LL) | ((x << 1) & 0xaaaaaaaaaaaaaaaaLL);
  x = ((x >> 2) & 0x3333333333333333LL) | ((x << 2) & 0xccccccccccccccccLL);
  x = ((x >> 4) & 0x0f0f0f0f0f0f0f0fLL) | ((x << 4) & 0xf0f0f0f0f0f0f0f0LL);
  x = ((x >> 8) & 0x00ff00ff00ff00ffLL) | ((x << 8) & 0xff00ff00ff00ff00LL);
  x = ((x >> 16) & 0x0000ffff0000ffffLL) | ((x << 16) & 0xffff0000ffff0000LL);
  x = ((x >> 32) & 0x00000000ffffffffLL) | ((x << 32) & 0xffffffff00000000LL);
  return x;
}
template <class T>
inline bool odd(T x) {
  return x & 1;
}
template <class T>
inline bool even(T x) {
  return !odd(x);
}
template <class T>
inline T low_bit(T x) {
  return x & -x;
}
template <class T>
inline T high_bit(T x) {
  T p = low_bit(x);
  while (p != x) x -= p, p = low_bit(x);
  return p;
}
template <class T>
inline T cover_bit(T x) {
  T p = 1;
  while (p < x) p <<= 1;
  return p;
}
template <class T>
inline int cover_idx(T x) {
  int p = 0;
  while (_1(p) < x) ++p;
  return p;
}
inline int clz(int x) { return __builtin_clz(x); }
inline int clz(long long x) { return __builtin_clzll(x); }
inline int ctz(int x) { return __builtin_ctz(x); }
inline int ctz(long long x) { return __builtin_ctzll(x); }
inline int lg2(int x) { return !x ? -1 : 31 - clz(x); }
inline int lg2(long long x) { return !x ? -1 : 63 - clz(x); }
inline int low_idx(int x) { return !x ? -1 : ctz(x); }
inline int low_idx(long long x) { return !x ? -1 : ctz(x); }
inline int high_idx(int x) { return lg2(x); }
inline int high_idx(long long x) { return lg2(x); }
inline int parity(int x) { return __builtin_parity(x); }
inline int parity(long long x) { return __builtin_parityll(x); }
inline int count_bits(int x) { return __builtin_popcount(x); }
inline int count_bits(long long x) { return __builtin_popcountll(x); }
}  // namespace BO
using namespace BO;
namespace CG {
inline double dist2(double x, double y) { return sqr(x) + sqr(y); }
struct Po {
  double x, y;
  Po(double x = 0, double y = 0) : x(x), y(y) {}
  void in() { RF(x, y); }
  void out() { printf("(%.2f,%.2f)", x, y); }
  inline friend istream &operator>>(istream &i, Po &p) {
    return i >> p.x >> p.y;
  }
  inline friend ostream &operator<<(ostream &o, Po p) {
    return o << "(" << p.x << ", " << p.y << ")";
  }
  Po operator-() const { return Po(-x, -y); }
  Po &operator+=(const Po &p) {
    x += p.x, y += p.y;
    return *this;
  }
  Po &operator-=(const Po &p) {
    x -= p.x, y -= p.y;
    return *this;
  }
  Po &operator*=(double k) {
    x *= k, y *= k;
    return *this;
  }
  Po &operator/=(double k) {
    x /= k, y /= k;
    return *this;
  }
  Po &operator*=(const Po &p) { return *this = *this * p; }
  Po &operator/=(const Po &p) { return *this = *this / p; }
  Po operator+(const Po &p) const { return Po(x + p.x, y + p.y); }
  Po operator-(const Po &p) const { return Po(x - p.x, y - p.y); }
  Po operator*(double k) const { return Po(x * k, y * k); }
  Po operator/(double k) const { return Po(x / k, y / k); }
  Po operator*(const Po &p) const {
    return Po(x * p.x - y * p.y, y * p.x + x * p.y);
  }
  Po operator/(const Po &p) const {
    return Po(x * p.x + y * p.y, y * p.x - x * p.y) / p.len2();
  }
  bool operator==(const Po &p) const { return !sgn(x, p.x) && !sgn(y, p.y); };
  bool operator!=(const Po &p) const { return sgn(x, p.x) || sgn(y, p.y); }
  bool operator<(const Po &p) const {
    return sgn(x, p.x) < 0 || !sgn(x, p.x) && sgn(y, p.y) < 0;
  }
  bool operator<=(const Po &p) const {
    return sgn(x, p.x) < 0 || !sgn(x, p.x) && sgn(y, p.y) <= 0;
  }
  bool operator>(const Po &p) const { return !(*this <= p); }
  bool operator>=(const Po &p) const { return !(*this < p); }
  double len2() const { return dist2(x, y); }
  double len() const { return sqrt(len2()); }
  double arg() const { return atan2(y, x); }
  Po &_1() { return *this /= len(); }
  Po &conj() {
    y = -y;
    return *this;
  }
  Po &lt() {
    swap(x, y), x = -x;
    return *this;
  }
  Po &rt() {
    swap(x, y), y = -y;
    return *this;
  }
  Po &rot(double a, const Po &o = Po()) {
    *this -= o;
    *this *= Po(cos(a), sin(a));
    return *this += o;
  }
};
inline double dot(double x1, double y1, double x2, double y2) {
  return x1 * x2 + y1 * y2;
}
inline double dot(const Po &a, const Po &b) { return dot(a.x, a.y, b.x, b.y); }
inline double dot(const Po &p0, const Po &p1, const Po &p2) {
  return dot(p1 - p0, p2 - p0);
}
inline double det(double x1, double y1, double x2, double y2) {
  return x1 * y2 - x2 * y1;
}
inline double det(const Po &a, const Po &b) { return det(a.x, a.y, b.x, b.y); }
inline double det(const Po &p0, const Po &p1, const Po &p2) {
  return det(p1 - p0, p2 - p0);
}
inline double ang(const Po &p0, const Po &p1) {
  return acos(dot(p0, p1) / p0.len() / p1.len());
}
inline double ang(const Po &p0, const Po &p1, const Po &p2) {
  return ang(p1 - p0, p2 - p0);
}
inline double ang(const Po &p0, const Po &p1, const Po &p2, const Po &p3) {
  return ang(p1 - p0, p3 - p2);
}
inline double dist2(const Po &a, const Po &b) {
  return dist2(a.x - b.x, a.y - b.y);
}
template <class T1, class T2>
inline int dett(const T1 &x, const T2 &y) {
  return sgn(det(x, y));
}
template <class T1, class T2, class T3>
inline int dett(const T1 &x, const T2 &y, const T3 &z) {
  return sgn(det(x, y, z));
}
template <class T1, class T2, class T3, class T4>
inline int dett(const T1 &x, const T2 &y, const T3 &z, const T4 &w) {
  return sgn(det(x, y, z, w));
}
template <class T1, class T2>
inline int dott(const T1 &x, const T2 &y) {
  return sgn(dot(x, y));
}
template <class T1, class T2, class T3>
inline int dott(const T1 &x, const T2 &y, const T3 &z) {
  return sgn(dot(x, y, z));
}
template <class T1, class T2, class T3, class T4>
inline int dott(const T1 &x, const T2 &y, const T3 &z, const T4 &w) {
  return sgn(dot(x, y, z, w));
}
template <class T1, class T2>
inline double arg(const T1 &x, const T2 &y) {
  double a = ang(x, y);
  return ~dett(x, y) ? a : 2 * PI - a;
}
template <class T1, class T2, class T3>
inline double arg(const T1 &x, const T2 &y, const T3 &z) {
  double a = ang(x, y, z);
  return ~dett(x, y, z) ? a : 2 * PI - a;
}
template <class T1, class T2, class T3, class T4>
inline double arg(const T1 &x, const T2 &y, const T3 &z, const T4 &w) {
  double a = ang(x, y, z, w);
  return ~dett(x, y, z, w) ? a : 2 * PI - a;
}
template <class T1, class T2>
inline double dist(const T1 &x, const T2 &y) {
  return sqrt(dist2(x, y));
}
template <class T1, class T2, class T3>
inline double dist(const T1 &x, const T2 &y, const T3 &z) {
  return sqrt(dist2(x, y, z));
}
inline Po _1(Po p) { return p._1(); }
inline Po conj(Po p) { return p.conj(); }
inline Po lt(Po p) { return p.lt(); }
inline Po rt(Po p) { return p.rt(); }
inline Po rot(Po p, double a, const Po &o = Po()) { return p.rot(a, o); }
inline Po operator*(double k, const Po &p) { return p * k; }
inline Po operator/(double k, const Po &p) { return conj(p) * k / p.len2(); }
struct Line {
  Po a, b;
  Line(const Po &a = Po(), const Po &b = Po()) : a(a), b(b) {}
  Line(double x0, double y0, double x1, double y1)
      : a(Po(x0, y0)), b(Po(x1, y1)) {}
  Line(const Line &l) : a(l.a), b(l.b) {}
  Line(double A, double B, double C) {
    C = -C;
    if (!::sgn(A))
      a = Po(0, C / B), b = Po(1, C / B);
    else if (!::sgn(B))
      a = Po(C / A, 0), b = Po(C / A, 1);
    else
      a = Po(0, C / B), b = Po(1, (C - A) / B);
  }
  void in() { a.in(), b.in(); }
  inline friend istream &operator>>(istream &i, Line &p) {
    return i >> p.a >> p.b;
  }
  inline friend ostream &operator<<(ostream &o, Line p) {
    return o << p.a << "-" << p.b;
  }
  Line operator+(const Po &x) const { return Line(a + x, b + x); }
  Line operator-(const Po &x) const { return Line(a - x, b - x); }
  Line operator*(double k) const { return Line(a * k, b * k); }
  Line operator/(double k) const { return Line(a / k, b / k); }
  Po operator*(const Line &) const;
  Po d() const { return b - a; }
  double len2() const { return d().len2(); }
  double len() const { return d().len(); }
  double arg() const { return d().arg(); }
  int sgn(const Po &p) const { return dett(a, b, p); }
  int sgn(const Line &) const;
  bool sameSgn(const Po &p1, const Po &p2) const { return sgn(p1) == sgn(p2); }
  void getEquation(double &K, double &B) const {
    K = ::sgn(a.x, b.x) ? (b.y - a.y) / (b.x - a.x) : OO;
    B = a.y - K * a.x;
  }
  void getEquation(double &A, double &B, double &C) const {
    A = a.y - b.y, B = b.x - a.x, C = det(a, b);
  }
  Line &push(double r) {
    Po v = d()._1().lt() * r;
    a += v, b += v;
    return *this;
  }
};
inline double dot(const Line &l1, const Line &l2) {
  return dot(l1.d(), l2.d());
}
inline double dot(const Line &l, const Po &p) { return dot(l.a, l.b, p); }
inline double dot(const Po &p, const Line &l) { return dot(p, l.a, l.b); }
inline double det(const Line &l1, const Line &l2) {
  return det(l1.d(), l2.d());
}
inline double det(const Line &l, const Po &p) { return det(l.a, l.b, p); }
inline double det(const Po &p, const Line &l) { return det(p, l.a, l.b); }
inline double ang(const Line &l0, const Line &l1) {
  return ang(l0.d(), l1.d());
}
inline double ang(const Line &l, const Po &p) { return ang(l.a, l.b, p); }
inline double ang(const Po &p, const Line &l) { return ang(p, l.a, l.b); }
inline int Line::sgn(const Line &l) const { return dett(*this, l); }
inline Po Line::operator*(const Line &l) const {
  return a + d() * det(a, l) / det(*this, l);
}
inline Po operator&(const Po &p, const Line &l) {
  return l * Line(p, p + l.d().lt());
}
inline Po operator%(const Po &p, const Line &l) { return p & l * 2 - p; }
inline Line push(Line l, double r) { return l.push(r); }
struct Seg : public Line {
  Seg(const Po &a = Po(), const Po &b = Po()) : Line(a, b) {}
  Seg(double x0, double y0, double x1, double y1) : Line(x0, y0, x1, y1) {}
  Seg(const Line &l) : Line(l) {}
  Seg(const Po &a, double alpha) : Line(a, alpha) {}
  Seg(double A, double B, double C) : Line(A, B, C) {}
  inline int sgn(const Po &p) const;
  inline int sgn(const Line &l) const;
  inline bool qrt(const Seg &l) const;
  inline int sgn(const Seg &l) const;
};
inline int Seg::sgn(const Po &p) const { return -dott(p, a, b); }
inline int Seg::sgn(const Line &l) const { return sgn(*this * l); }
inline bool Seg::qrt(const Seg &l) const {
  return min(a.x, b.x) <= max(l.a.x, l.b.x) &&
         min(l.a.x, l.b.x) <= max(a.x, b.x) &&
         min(a.y, b.y) <= max(l.a.y, l.b.y) &&
         min(l.a.y, l.b.y) <= max(a.y, b.y);
}
inline int Seg::sgn(const Seg &l) const {
  if (!qrt(l)) return -1;
  int d1 = dett(a, b, l.a), d2 = dett(a, b, l.b), d3 = dett(l.a, l.b, a),
      d4 = dett(l.a, l.b, b);
  if ((d1 ^ d2) == -2 && (d3 ^ d4) == -2) return 1;
  return ((!d1 && dott(l.a - a, l.a - b) <= 0) ||
          (!d2 && dott(l.b - a, l.b - b) <= 0) ||
          (!d3 && dott(a - l.a, a - l.b) <= 0) ||
          (!d4 && dott(b - l.a, b - l.b) <= 0))
             ? 0
             : -1;
}
inline double dist2(const Line &l, const Po &p) {
  return sqr(fabs(det(l.d(), p - l.a))) / l.len2();
}
inline double dist2(const Line &l1, const Line &l2) {
  return dett(l1, l2) ? 0 : dist2(l1, l2.a);
}
inline double dist2(const Seg &l, const Po &p) {
  Po pa = p - l.a, pb = p - l.b;
  if (dott(l.d(), pa) <= 0) return pa.len2();
  if (dott(l.d(), pb) >= 0) return pb.len2();
  return dist2(Line(l), p);
}
inline double dist2(const Seg &s, const Line &l) {
  Po v1 = s.a - l.a, v2 = s.b - l.a;
  double d1 = det(l.d(), v1), d2 = det(l.d(), v2);
  return sgn(d1) != sgn(d2) ? 0 : sqr(min(fabs(d1), fabs(d2))) / l.len2();
}
inline double dist2(const Seg &l1, const Seg &l2) {
  if (~l1.sgn(l2))
    return 0;
  else
    return min(dist2(l2, l1.a), dist2(l2, l1.b), dist2(l1, l2.a),
               dist2(l1, l2.b));
}
template <class T1, class T2>
inline double dist2(const T1 &a, const T2 &b) {
  return dist2(b, a);
}
}  // namespace CG
using namespace CG;
template <class T>
inline T &RD(T &x) {
  char c;
  while (!isdigit((c = getchar())))
    ;
  x = c - '0';
  while (isdigit((c = getchar()))) x = x * 10 + c - '0';
  return x;
}
template <class T>
inline T &RDD(T &x) {
  char c;
  while ((c = getchar()), c != '-' && !isdigit(c))
    ;
  if (c == '-') {
    x = '0' - (c = getchar());
    while (isdigit((c = getchar()))) x = x * 10 + '0' - c;
  } else {
    x = c - '0';
    while (isdigit((c = getchar()))) x = x * 10 + c - '0';
  }
  return x;
}
inline double &RF(double &x) {
  char c;
  while ((c = getchar()), c != '-' && c != '.' && !isdigit(c))
    ;
  if (c == '-')
    if ((c = getchar()) == '.') {
      x = 0;
      double l = 1;
      while (isdigit((c = getchar()))) l /= 10, x = x * 10 + '0' - c;
      x *= l;
    } else {
      x = '0' - c;
      while (isdigit((c = getchar()))) x = x * 10 + '0' - c;
      if (c == '.') {
        double l = 1;
        while (isdigit((c = getchar()))) l /= 10, x = x * 10 + '0' - c;
        x *= l;
      }
    }
  else if (c == '.') {
    x = 0;
    double l = 1;
    while (isdigit((c = getchar()))) l /= 10, x = x * 10 + c - '0';
    x *= l;
  } else {
    x = c - '0';
    while (isdigit((c = getchar()))) x = x * 10 + c - '0';
    if (c == '.') {
      double l = 1;
      while (isdigit((c = getchar()))) l /= 10, x = x * 10 + c - '0';
      x *= l;
    }
  }
  return x;
}
inline char *RS(char *s) {
  scanf("%s", s);
  return s;
}
long long last_ans;
int Case;
template <class T>
inline void OT(const T &x) {
  printf("%d\n", x);
}
const int N = int(1e6) + 9;
bool vis[N * 2];
char S[N];
int A[N];
int n, nn;
bool ck(int o) {
  int l = 0, r = 0, x = 0;
  for (int i = 0; i < nn; ++i) {
    x += A[i];
    checkMax(x, o + 1);
    checkMin(l, x);
    checkMax(r, x);
  }
  return x + A[nn] > r;
}
int main() {
  n = strlen(RS(S));
  A[0] = S[0] == 'R' ? 1 : -1;
  for (int i = 1; i < n; ++i)
    if (S[i] == 'R') {
      if (A[nn] > 0)
        ++A[nn];
      else if (A[nn] < 0)
        ++A[++nn];
    } else {
      if (A[nn] < 0)
        --A[nn];
      else if (A[nn] > 0)
        --A[++nn];
    }
  if (A[nn] < 0) {
    for (int i = 0; i < nn + 1; ++i) A[i] = -A[i];
  }
  int l = 0, r = 0, x = 0;
  for (int i = 0; i < nn; ++i) {
    x += A[i];
    checkMin(l, x);
    checkMax(r, x);
  }
  if (x + A[nn] > r) {
    OT(1);
    return 0;
  }
  l = 0, r = n;
  while (l < r) {
    int m = (l + r + 1) / 2;
    if (ck(-m))
      l = m;
    else
      r = m - 1;
  }
  cout << l << endl;
}