#include <bits/stdc++.h>
long long dx[8] = {0, 1, 0, -1, 1, 1, -1, -1};
long long dy[8] = {1, 0, -1, 0, -1, 1, 1, -1};
using namespace std;
class pa3 {
 public:
  long long x;
  long long y, z;
  pa3(long long x = 0, long long y = 0, long long z = 0) : x(x), y(y), z(z) {}
  bool operator<(const pa3 &p) const {
    if (x != p.x) return x < p.x;
    if (y != p.y) return y < p.y;
    return z < p.z;
  }
  bool operator>(const pa3 &p) const {
    if (x != p.x) return x > p.x;
    if (y != p.y) return y > p.y;
    return z > p.z;
  }
  bool operator==(const pa3 &p) const {
    return x == p.x && y == p.y && z == p.z;
  }
  bool operator!=(const pa3 &p) const {
    return !(x == p.x && y == p.y && z == p.z);
  }
};
class pa4 {
 public:
  long long x;
  long long y, z, w;
  pa4(long long x = 0, long long y = 0, long long z = 0, long long w = 0)
      : x(x), y(y), z(z), w(w) {}
  bool operator<(const pa4 &p) const {
    if (x != p.x) return x < p.x;
    if (y != p.y) return y < p.y;
    if (z != p.z) return z < p.z;
    return w < p.w;
  }
  bool operator>(const pa4 &p) const {
    if (x != p.x) return x > p.x;
    if (y != p.y) return y > p.y;
    if (z != p.z) return z > p.z;
    return w > p.w;
  }
  bool operator==(const pa4 &p) const {
    return x == p.x && y == p.y && z == p.z && w == p.w;
  }
};
class pa2 {
 public:
  long long x, y;
  pa2(long long x = 0, long long y = 0) : x(x), y(y) {}
  pa2 operator+(pa2 p) { return pa2(x + p.x, y + p.y); }
  pa2 operator-(pa2 p) { return pa2(x - p.x, y - p.y); }
  bool operator<(const pa2 &p) const { return y != p.y ? y < p.y : x < p.x; }
  bool operator>(const pa2 &p) const { return x != p.x ? x < p.x : y < p.y; }
  bool operator==(const pa2 &p) const {
    return abs(x - p.x) == 0 && abs(y - p.y) == 0;
  }
  bool operator!=(const pa2 &p) const {
    return !(abs(x - p.x) == 0 && abs(y - p.y) == 0);
  }
};
class Point {
 public:
  double x, y;
  Point(double x = 0, double y = 0) : x(x), y(y) {}
  Point operator+(Point p) { return Point(x + p.x, y + p.y); }
  Point operator-(Point p) { return Point(x - p.x, y - p.y); }
  Point operator*(double a) { return Point(x * a, y * a); }
  Point operator/(double a) { return Point(x / a, y / a); }
  double absv() { return sqrt(norm()); }
  double norm() { return x * x + y * y; }
  bool operator<(const Point &p) const { return x != p.x ? x < p.x : y < p.y; }
  bool operator==(const Point &p) const {
    return fabs(x - p.x) < (1e-10) && fabs(y - p.y) < (1e-10);
  }
};
struct Segment {
  Point p1, p2;
};
double dot(Point a, Point b) { return a.x * b.x + a.y * b.y; }
double cross(Point a, Point b) { return a.x * b.y - a.y * b.x; }
bool parareru(Point a, Point b, Point c, Point d) {
  return abs(cross(a - b, d - c)) < (1e-10);
}
double distance_ls_p(Point a, Point b, Point c) {
  if (dot(b - a, c - a) < (1e-10)) return (c - a).absv();
  if (dot(a - b, c - b) < (1e-10)) return (c - b).absv();
  return abs(cross(b - a, c - a)) / (b - a).absv();
}
bool is_intersected_ls(Segment a, Segment b) {
  if (a.p1 == b.p1 || a.p2 == b.p1 || a.p1 == b.p2 || a.p2 == b.p2)
    return false;
  if (parareru((a.p2), (a.p1), (a.p1), (b.p2)) &&
      parareru((a.p2), (a.p1), (a.p1), (b.p1))) {
    if (dot(a.p1 - b.p1, a.p1 - b.p2) < (1e-10)) return true;
    if (dot(a.p2 - b.p1, a.p2 - b.p2) < (1e-10)) return true;
    if (dot(a.p1 - b.p1, a.p2 - b.p1) < (1e-10)) return true;
    if (dot(a.p1 - b.p2, a.p2 - b.p2) < (1e-10)) return true;
    return false;
  } else
    return (cross(a.p2 - a.p1, b.p1 - a.p1) * cross(a.p2 - a.p1, b.p2 - a.p1) <
            (1e-10)) &&
           (cross(b.p2 - b.p1, a.p1 - b.p1) * cross(b.p2 - b.p1, a.p2 - b.p1) <
            (1e-10));
}
double segment_dis(Segment a, Segment b) {
  if (is_intersected_ls(a, b)) return 0;
  double r = distance_ls_p(a.p1, a.p2, b.p1);
  r = min(r, distance_ls_p(a.p1, a.p2, b.p2));
  r = min(r, distance_ls_p(b.p1, b.p2, a.p2));
  r = min(r, distance_ls_p(b.p1, b.p2, a.p1));
  return r;
}
Point intersection_ls(Segment a, Segment b) {
  Point ba = b.p2 - b.p1;
  double d1 = abs(cross(ba, a.p1 - b.p1));
  double d2 = abs(cross(ba, a.p2 - b.p1));
  double t = d1 / (d1 + d2);
  return a.p1 + (a.p2 - a.p1) * t;
}
string itos(long long i) {
  ostringstream s;
  s << i;
  return s.str();
}
long long gcd(long long v, long long b) {
  if (v > b) return gcd(b, v);
  if (v == b) return b;
  if (b % v == 0) return v;
  return gcd(v, b % v);
}
double distans(double x1, double y1, double x2, double y2) {
  double rr = (x1 - x2) * (x1 - x2) + (y1 - y2) * (y1 - y2);
  return sqrt(rr);
}
long long mod;
long long extgcd(long long a, long long b, long long &x, long long &y) {
  if (b == 0) {
    x = 1;
    y = 0;
    return a;
  }
  long long d = extgcd(b, a % b, y, x);
  y -= a / b * x;
  return d;
}
pair<long long, long long> operator+(const pair<long long, long long> &l,
                                     const pair<long long, long long> &r) {
  return {l.first + r.first, l.second + r.second};
}
long long pr[1200010];
long long inv[1200010];
long long beki(long long wa, long long rr, long long warukazu) {
  if (rr == 0) return 1 % warukazu;
  if (rr == 1) return wa % warukazu;
  wa %= warukazu;
  if (rr % 2 == 1)
    return ((long long)beki(wa, rr - 1, warukazu) * (long long)wa) % warukazu;
  long long zx = beki(wa, rr / 2, warukazu);
  return (zx * zx) % warukazu;
}
double bekid(double w, long long r) {
  if (r == 0) return 1.0;
  if (r == 1) return w;
  if (r % 2) return bekid(w, r - 1) * w;
  double f = bekid(w, r / 2);
  return f * f;
}
long long comb(long long nn, long long rr) {
  long long r = pr[nn] * inv[rr];
  r %= mod;
  r *= inv[nn - rr];
  r %= mod;
  return r;
}
void gya(long long ert) {
  pr[0] = 1;
  for (long long i = 1; i <= ert; i++) {
    pr[i] = (pr[i - 1] * i) % mod;
  }
  for (long long i = 0; i <= ert; i++) inv[i] = beki(pr[i], mod - 2, mod);
}
struct seg_rangeadd_getmin {
 private:
 public:
  long long cor = (1 << 19);
  long long inff = (long long)1000000007 * (long long)1000000007;
  vector<long long> vec;
  vector<long long> lazy;
  void shoki1() {
    vec.resize(2 * cor + 3, 0);
    lazy.resize(2 * cor + 3, 0);
  }
  void shoki2() {
    for (long long i = cor - 1; i > 0; i--) {
      vec[i] = min(vec[2 * i], vec[2 * i + 1]);
    }
  }
  void chien(long long k, long long l, long long r) {
    if (l + 1 < r) {
      vec[k] += lazy[k];
      lazy[2 * k] += lazy[k];
      lazy[2 * k + 1] += lazy[k];
      lazy[k] = 0;
    } else {
      vec[k] += lazy[k];
      lazy[k] = 0;
    }
  }
  long long rangeadd(long long a, long long b, long long w, long long k = 1,
                     long long l = 0, long long r = -3) {
    if (r < 0) r = cor;
    if (a <= l && r <= b) {
      lazy[k] += w;
      chien(k, l, r);
      return vec[k];
    }
    if (r <= a || b <= l) {
      chien(k, l, r);
      return vec[k];
    }
    chien(k, l, r);
    long long w1 = rangeadd(a, b, w, k * 2, l, (l + r) / 2);
    long long w2 = rangeadd(a, b, w, k * 2 + 1, (l + r) / 2, r);
    vec[k] = min(w1, w2);
    return vec[k];
  }
  long long getmin(long long a, long long b, long long k = 1, long long l = 0,
                   long long r = -1) {
    if (r < 0) r = cor;
    chien(k, l, r);
    if (r <= a || b <= l) {
      return inff;
    }
    if (a <= l && r <= b) {
      return vec[k];
    }
    long long w1 = getmin(a, b, k * 2, l, (l + r) / 2);
    long long w2 = getmin(a, b, k * 2 + 1, (l + r) / 2, r);
    return min(w1, w2);
  }
  void pre() {
    for (long long i = 1; i < 2 * cor; i++) {
      cout << vec[i] << " ";
      if (((i + 1) & (-(i + 1))) == i + 1) cout << endl;
    }
  }
};
seg_rangeadd_getmin ss;
vector<pair<long long, long long> > G[500020];
vector<long long> ve;
long long lef[500020], rig[500020];
long long dis[500020];
void f_dfs(long long r) {
  lef[r] = ve.size();
  if (G[r].size()) {
    for (auto v : G[r]) f_dfs(v.first);
  } else
    ve.push_back(r);
  rig[r] = ve.size();
}
void s_dfs(long long r, long long d = 0) {
  dis[r] = d;
  for (auto v : G[r]) {
    s_dfs(v.first, v.second + d);
  }
}
vector<pa3> que[500020];
long long ans[500020];
long long ha = 0;
long long zen = 0;
void dfs(long long r) {
  for (auto v : que[r]) {
    long long lq = lower_bound(ve.begin(), ve.end(), v.x) - ve.begin();
    long long rq = lower_bound(ve.begin(), ve.end(), v.y) - ve.begin();
    long long t = ss.getmin(lq, rq);
    ans[v.z] = t + zen;
  }
  for (auto v : G[r]) {
    zen += v.second;
    ss.rangeadd(lef[v.first], rig[v.first], -2 * v.second);
    dfs(v.first);
    zen -= v.second;
    ss.rangeadd(lef[v.first], rig[v.first], 2 * v.second);
  }
}
signed main() {
  cin.tie(0);
  ios::sync_with_stdio(false);
  long long n, q;
  cin >> n >> q;
  for (long long i = 2; i <= n; i++) {
    long long y, yy;
    cin >> y >> yy;
    G[y].push_back({i, yy});
  }
  for (long long i = 0; i < q; i++) {
    long long y, yy, yyy;
    cin >> yyy >> y >> yy;
    yy++;
    que[yyy].push_back({y, yy, i});
  }
  f_dfs(1);
  s_dfs(1);
  ss.shoki1();
  long long cnt = 0;
  for (long long i = 1; i <= n; i++) {
    if (G[i].size()) {
    } else {
      ss.vec[ss.cor + cnt] = dis[i], ha++;
      cnt++;
    }
  }
  ss.shoki2();
  dfs(1);
  for (long long i = 0; i < q; i++) cout << ans[i] << "\n";
  return 0;
}
