Problem p03427 (C++)

Buggy submission (status: Runtime Error):
#include <algorithm>
#include <bitset>
#include <cctype>
#include <cmath>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <ctime>
#include <deque>
#include <functional>
#include <iomanip>
#include <iostream>
#include <list>
#include <map>
#include <numeric>
#include <queue>
#include <set>
#include <sstream>
#include <stack>
#include <string>
#include <utility>
#include <vector>
using namespace std;

// conversion
//------------------------------------------
inline int toInt(string s) {
  int v;
  istringstream sin(s);
  sin >> v;
  return v;
}
template <class T> inline string toString(T x) {
  ostringstream sout;
  sout << x;
  return sout.str();
}

// math
//-------------------------------------------
template <class T> inline T sqr(T x) { return x * x; }

// typedef
//------------------------------------------
typedef vector<int> VI;
typedef vector<VI> VVI;
typedef vector<string> VS;
typedef pair<int, int> PII;
typedef long long LL;

// container util
//------------------------------------------
#define ALL(a) (a).begin(), (a).end()
#define RALL(a) (a).rbegin(), (a).rend()
#define PB push_back
#define MP make_pair
#define SZ(a) int((a).size())
#define EACH(i, c)                                                             \
  for (typeof((c).begin()) i = (c).begin(); i != (c).end(); ++i)
#define EXIST(s, e) ((s).find(e) != (s).end())
#define SORT(c) sort((c).begin(), (c).end())

// repetition
//------------------------------------------
#define FOR(i, a, b) for (int i = (a); i < (b); ++i)
#define REP(i, n) FOR(i, 0, n)

// constant
//--------------------------------------------
const double EPS = 1e-10;
const double PI = acos(-1.0);

// clear memory
#define CLR(a) memset((a), 0, sizeof(a))

// debug
#define dump(x) cerr << #x << '=' << (x) << endl;
#define debug(x)                                                               \
  cerr << #x << '=' << (x) << '(' << 'L' << __LINE__ << ')' << ' ' << __FILE__ \
       << endl;

#define YES_                                                                   \
  cout << "YES" << endl;                                                       \
  return 0;
#define NO_                                                                    \
  cout << "NO" << endl;                                                        \
  return 0;

int main() {

  string S;
  LL ans = 0LL;

  cin >> S;
  int n = S.size();

  LL jimei = 9 * (S.size() - 1);

  if (S[0] != '9') {

    // 先頭が何かの数字かつ下の桁がすべて9ならその数字が答え
    FOR(i, 1, S.size()) {
      if (S[i] != '9') {
        goto NEXT;
      }
    }
    FOR(i, 0, S.size()) { ans += LL(S[i] - '0'); }
    cout << max(ans, jimei) << endl;
    return 0;

  NEXT:;
    // したがすべて９ではなかった
    ans += S[0] - '1';
    REP(i, S.size() - 1) { ans += 9; }
    cout << max(ans, jimei) << endl;
    return 0;
  }
  // 先頭が9だった
  else {

    FOR(i, 1, S.size()) {
      if (S[i] != '9') {
        goto NONALL;
      }
    }
    // 全て9
    REP(i, S.size()) { ans += 9; }
    cout << max(ans, jimei) << endl;

    return ans;

  NONALL:;
    ans += 8;
    FOR(i, 1, S.size()) { ans += 9; }

    cout << max(ans, jimei) << endl;
    return 0;
  }
}


Fixed submission:
#include <algorithm>
#include <bitset>
#include <cctype>
#include <cmath>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <ctime>
#include <deque>
#include <functional>
#include <iomanip>
#include <iostream>
#include <list>
#include <map>
#include <numeric>
#include <queue>
#include <set>
#include <sstream>
#include <stack>
#include <string>
#include <utility>
#include <vector>
using namespace std;

// conversion
//------------------------------------------
inline int toInt(string s) {
  int v;
  istringstream sin(s);
  sin >> v;
  return v;
}
template <class T> inline string toString(T x) {
  ostringstream sout;
  sout << x;
  return sout.str();
}

// math
//-------------------------------------------
template <class T> inline T sqr(T x) { return x * x; }

// typedef
//------------------------------------------
typedef vector<int> VI;
typedef vector<VI> VVI;
typedef vector<string> VS;
typedef pair<int, int> PII;
typedef long long LL;

// container util
//------------------------------------------
#define ALL(a) (a).begin(), (a).end()
#define RALL(a) (a).rbegin(), (a).rend()
#define PB push_back
#define MP make_pair
#define SZ(a) int((a).size())
#define EACH(i, c)                                                             \
  for (typeof((c).begin()) i = (c).begin(); i != (c).end(); ++i)
#define EXIST(s, e) ((s).find(e) != (s).end())
#define SORT(c) sort((c).begin(), (c).end())

// repetition
//------------------------------------------
#define FOR(i, a, b) for (int i = (a); i < (b); ++i)
#define REP(i, n) FOR(i, 0, n)

// constant
//--------------------------------------------
const double EPS = 1e-10;
const double PI = acos(-1.0);

// clear memory
#define CLR(a) memset((a), 0, sizeof(a))

// debug
#define dump(x) cerr << #x << '=' << (x) << endl;
#define debug(x)                                                               \
  cerr << #x << '=' << (x) << '(' << 'L' << __LINE__ << ')' << ' ' << __FILE__ \
       << endl;

#define YES_                                                                   \
  cout << "YES" << endl;                                                       \
  return 0;
#define NO_                                                                    \
  cout << "NO" << endl;                                                        \
  return 0;

int main() {

  string S;
  LL ans = 0LL;

  cin >> S;
  int n = S.size();

  LL jimei = 9 * (S.size() - 1);

  if (S[0] != '9') {

    // 先頭が何かの数字かつ下の桁がすべて9ならその数字が答え
    FOR(i, 1, S.size()) {
      if (S[i] != '9') {
        goto NEXT;
      }
    }
    FOR(i, 0, S.size()) { ans += LL(S[i] - '0'); }
    cout << max(ans, jimei) << endl;
    return 0;

  NEXT:;
    // したがすべて９ではなかった
    ans += S[0] - '1';
    REP(i, S.size() - 1) { ans += 9; }
    cout << max(ans, jimei) << endl;
    return 0;
  }
  // 先頭が9だった
  else {

    FOR(i, 1, S.size()) {
      if (S[i] != '9') {
        goto NONALL;
      }
    }
    // 全て9
    REP(i, S.size()) { ans += 9; }
    cout << max(ans, jimei) << endl;

    return 0;

  NONALL:;
    ans += 8;
    FOR(i, 1, S.size()) { ans += 9; }

    cout << max(ans, jimei) << endl;
    return 0;
  }
}