func_code_string: #include <bits/stdc++.h>   using namespace std;   const int MAXN = 1e5 + 10;   int l = 1, r = 0;   int a[MAXN], b[MAXN], now[MAXN], num[MAXN << 1], cnt[MAXN], ans[MAXN];   map<int, int> ms;   struct Change {     int p, x, y;   } c[MAXN];   struct Query {     int l, r, t, id;     bool operator<(const Query &A) const {       if (b[l] == b[A.l]) return b[r] == b[A.r] ? t < A.t : b[r] < b[A.r];       return b[l] < b[A.l];     }   } q[MAXN];   void update(int x, int d) {     int &y = num[x];     if (y > 0) cnt[y]--;     y += d;     if (y > 0) cnt[y]++;   }   void modify(int p, int d) {     if (l <= p && p <= r) {       update(a[p], -1);       update(d, 1);     }     a[p] = d;   }   int get() {     for (int i = 1;; i++) {       if (!cnt[i]) return i;     }   }   int main() {     int n, m, id = 0, Time = 0, sz = 0;     scanf( %d%d , &n, &m);     int B = 2000;     for (int i = 1; i <= n; i++) {       scanf( %d , &a[i]);       int &t = ms[a[i]];       if (!t) t = ++sz;       now[i] = a[i] = t;       b[i] = i / B + 1;     }     while (m--) {       int op, x, y;       scanf( %d%d%d , &op, &x, &y);       if (op == 1)         q[++id] = (Query){x, y, Time, id};       else {         int &t = ms[y];         if (!t) t = ++sz;         c[++Time] = (Change){x, y = t, now[x]};         now[x] = y;       }     }     sort(q + 1, q + id + 1);     int v = 0;     for (int i = 1; i <= id; i++) {       while (v < q[i].t) modify(c[v + 1].p, c[v + 1].x), v++;       while (v > q[i].t) modify(c[v].p, c[v].y), v--;       while (l < q[i].l) update(a[l], -1), l++;       while (l > q[i].l) update(a[l - 1], 1), l--;       while (r < q[i].r) update(a[r + 1], 1), r++;       while (r > q[i].r) update(a[r], -1), r--;       ans[q[i].id] = get();     }     for (int i = 1; i <= id; i++) {       printf( %d n , ans[i]);     }     return 0;   }   