Problem p00430 (C++)

Buggy submission (status: Runtime Error):
#include <algorithm>
#include <array>
#include <cmath>
#include <complex>
#include <cstdio>
#include <cstring>
#include <functional>
#include <iostream>
#include <limits.h>
#include <map>
#include <numeric>
#include <queue>
#include <random>
#include <set>
#include <stack>
#include <unordered_map>
#include <vector>
#define rep(i, s, n) for (int i = (s); (n) > i; i++)
#define REP(i, n) rep(i, 0, n)
#define RANGE(x, a, b) ((a) <= (x) && (x) <= (b))
#define DUPLE(a, b, c, d)                                                      \
  (RANGE(a, c, d) || RANGE(b, c, d) || RANGE(c, a, b) || RANGE(d, a, b))
#define INCLU(a, b, c, d) (RANGE(a, c, d) && (b, c, d))
#define PW(x) ((x) * (x))
#define ALL(x) (x).begin(), (x).end()
#define RALL(x) (x).rbegin(), (x).rend()
#define MODU 1000000007
#define bitcheck(a, b) ((a >> b) & 1)
#define bitset(a, b) (a |= (1 << b))
#define bitunset(a, b) (a &= ~(1 << b))
#define MP(a, b) make_pair((a), (b))
#define Manh(a, b) (abs((a).first-(b).first) + abs((a).second - ((b).second))
#define pritnf printf
#define scnaf scanf
#define itn int
#define PI 3.141592653589

#define izryt bool

using namespace std;
typedef long long ll;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
template <typename A, size_t N, typename T>
void Fill(A (&array)[N], const T &val) {
  std::fill((T *)array, (T *)(array + N), val);
}
pii Dir[8] = { //?§????
    {0, 1}, {-1, 0}, {1, 0}, {0, -1}, {1, 1}, {1, -1}, {-1, 1}, {-1, -1}};

signed main() {
  int n;
  while (scanf("%d", &n)) {
    if (!n)
      break;
    vector<int> used;
    function<void(int, int)> func = [&](int sum, int bef) {
      if (sum == n) {
        REP(i, used.size()) {
          printf("%d", used[i]);
          if (i != (int)used.size() - 1)
            printf(" ");
        }
        printf("\n");
        return;
      }
      for (int i = bef; 0 <= i; i--) {
        if (sum + i <= n) {
          used.push_back(i);
          func(sum + i, i);
          used.erase(--used.end());
        }
      }
    };

    func(0, n);
  }
  return 0;
}

Fixed submission:
#include <algorithm>
#include <array>
#include <cmath>
#include <complex>
#include <cstdio>
#include <cstring>
#include <functional>
#include <iostream>
#include <limits.h>
#include <map>
#include <numeric>
#include <queue>
#include <random>
#include <set>
#include <stack>
#include <unordered_map>
#include <vector>
#define rep(i, s, n) for (int i = (s); (n) > i; i++)
#define REP(i, n) rep(i, 0, n)
#define RANGE(x, a, b) ((a) <= (x) && (x) <= (b))
#define DUPLE(a, b, c, d)                                                      \
  (RANGE(a, c, d) || RANGE(b, c, d) || RANGE(c, a, b) || RANGE(d, a, b))
#define INCLU(a, b, c, d) (RANGE(a, c, d) && (b, c, d))
#define PW(x) ((x) * (x))
#define ALL(x) (x).begin(), (x).end()
#define RALL(x) (x).rbegin(), (x).rend()
#define MODU 1000000007
#define bitcheck(a, b) ((a >> b) & 1)
#define bitset(a, b) (a |= (1 << b))
#define bitunset(a, b) (a &= ~(1 << b))
#define MP(a, b) make_pair((a), (b))
#define Manh(a, b) (abs((a).first-(b).first) + abs((a).second - ((b).second))
#define pritnf printf
#define scnaf scanf
#define itn int
#define PI 3.141592653589

#define izryt bool

using namespace std;
typedef long long ll;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
template <typename A, size_t N, typename T>
void Fill(A (&array)[N], const T &val) {
  std::fill((T *)array, (T *)(array + N), val);
}
pii Dir[8] = { //?§????
    {0, 1}, {-1, 0}, {1, 0}, {0, -1}, {1, 1}, {1, -1}, {-1, 1}, {-1, -1}};

signed main() {
  int n;
  while (scanf("%d", &n)) {
    if (!n)
      break;
    vector<int> used;
    function<void(int, int)> func = [&](int sum, int bef) {
      if (sum == n) {
        REP(i, used.size()) {
          printf("%d", used[i]);
          if (i != (int)used.size() - 1)
            printf(" ");
        }
        printf("\n");
        return;
      }
      for (int i = bef; 1 <= i; i--) {
        if (sum + i <= n) {
          used.push_back(i);
          func(sum + i, i);
          used.erase(--used.end());
        }
      }
    };

    func(0, n);
  }
  return 0;
}