#include <bits/stdc++.h>
using namespace std;
namespace jyy {
const int mod = 998244353, N = 20010;
const double eps = 1e-8;
inline int read() {
  static int x = 0, f = 1;
  x = 0, f = 1;
  static char ch = getchar();
  while (ch < '0' || ch > '9') {
    (ch == '-') ? f *= -1 : f;
    ch = getchar();
  }
  while (ch >= '0' && ch <= '9') x = x * 10 + int(ch - 48), ch = getchar();
  return x * f;
}
inline void fw(int x) {
  if (x < 0) putchar('-'), x = -x;
  x >= 10 ? fw(x / 10), 1 : 0;
  putchar(char(x % 10 + 48));
}
int qmo(int x) { return x + ((x >> 31) & mod); }
int ksm(int x, int y) {
  int tmp = 1, sum = x;
  while (y) {
    if (y & 1) tmp = 1ll * tmp * sum % mod;
    sum = 1ll * sum * sum % mod;
    y >>= 1;
  }
  return tmp;
}
int inv(int x) { return ksm(x, mod - 2); }
int tot, head[N], fa[N];
struct edge {
  int to, next;
} dat[N * 2];
void add_edge(int x, int y) { dat[++tot] = (edge){y, head[x]}, head[x] = tot; }
int find(int x) { return fa[x] ? fa[x] = find(fa[x]) : x; }
void merge(int x, int y) { find(x) != find(y) ? fa[find(x)] = find(y) : 0; }
int low(int x) { return x & -x; }
}  // namespace jyy
using namespace jyy;
int lg2[N], st[18][N], dp[N][18][31], now[N], tmp[N], a[N], n, m;
int query(int l, int r) {
  int k = lg2[r - l + 1];
  if (a[st[k][l]] + st[k][l] >
      a[st[k][r - (1 << k) + 1]] + st[k][r - (1 << k) + 1])
    return st[k][l];
  return st[k][r - (1 << k) + 1];
}
int main() {
  cin >> n >> m;
  lg2[0] = -1;
  for (int i = 1; i <= n; i++)
    a[i] = read(), st[0][i] = i, lg2[i] = lg2[i >> 1] + 1;
  for (int i = 1; i <= 17; i++)
    for (int j = 1; j <= n; j++)
      if (j + (1 << i) - 1 <= n) {
        if (a[st[i - 1][j]] + st[i - 1][j] >
            a[st[i - 1][j + (1 << (i - 1))]] + st[i - 1][j + (1 << (i - 1))])
          st[i][j] = st[i - 1][j];
        else
          st[i][j] = st[i - 1][j + (1 << (i - 1))];
      }
  for (int i = 1; i <= n; i++)
    for (int j = 0; j <= 30; j++) dp[i][0][j] = i + a[i] + j;
  for (int j = 1; j <= 17; j++)
    for (int i = 1; i <= n; i++)
      for (int k = 0; k <= 30; k++)
        for (int w = 0; w <= k; w++) {
          if (dp[i][j - 1][w] > n || dp[i][j - 1][k] > n) {
            dp[i][j][k] = n + 1;
            break;
          }
          dp[i][j][k] =
              max(dp[query(i, dp[i][j - 1][w])][j - 1][k - w], dp[i][j][k]);
        }
  while (m--) {
    int l = read(), r = read(), k = read(), ans = 0;
    if (r - l + 1 - k <= 1) {
      puts("0");
      continue;
    }
    for (int i = 0; i <= k; i++) now[i] = tmp[i] = l;
    for (int i = 17; i >= 0; i--) {
      for (int j = 0; j <= k; j++) tmp[j] = now[j];
      for (int j = 0; j <= k; j++) {
        for (int w = 0; w <= j; w++) {
          tmp[j] = max(tmp[j], dp[query(l, now[w])][i][j - w]);
        }
      }
      int flag = 0;
      for (int j = 0; j <= k; j++)
        if (tmp[j] >= r) flag = 1;
      if (flag) continue;
      ans += (1 << i);
      for (int j = 0; j <= k; j++) now[j] = tmp[j];
    }
    fw(ans + 1), putchar('\n');
  }
}
