#include <bits/stdc++.h>
int main() {
  int n;
  scanf("%d", &n);
  int vec = 0, p1 = 0x7fffffff, p2 = 0x7fffffff, i0 = -1, i1 = -1, i2 = -1;
  bool solved = (n <= 2);
  for (int i = 0; i < n; i++) {
    int v;
    scanf("%d", &v);
    if (solved) {
      continue;
    }
    if (i != 0) {
      if (vec == 0 && v != p1) {
        vec = (v > p1) ? 1 : -1;
      }
      if (vec > 0) {
        if (v < p1) {
          i0 = i;
          solved = true;
          continue;
        }
      } else if (vec < 0) {
        if (v > p1) {
          i0 = i;
          solved = true;
          continue;
        }
      }
    }
    if (p1 != v) {
      p2 = p1;
      p1 = v;
      i2 = i1;
      i1 = i;
    }
  }
  if (solved && n > 2) {
    printf("3\n%d %d %d\n", i2 + 1, i1 + 1, i0 + 1);
  } else {
    printf("0\n");
  }
  return 0;
}
