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时间限制: 5.0 s 内存限制: 1024 MB 总分: 100 可 Hack ✓

#9694. 浅酌低唱

统计

有一个长度为 $n$ 的二进制序列,你需要执行 $q$ 次操作。操作如下:

  1. 对于区间 $[\ell, r]$,同时将区间内每一个相邻的 $01$ 对变为 $10$。
  2. 对于区间 $[\ell, r]$,同时将区间内每一个相邻的 $10$ 对变为 $01$。
  3. 查询区间 $[\ell, r]$ 中 $1$ 的个数。

输入格式

第一行包含两个整数 $n$ 和 $q$ ($1 \le n \le 2 \cdot 10^6$; $1 \le q \le 2.5 \cdot 10^5$)。 下一行包含一个长度为 $n$ 的二进制字符串:初始的二进制序列。 接下来的 $q$ 行,每行包含三个整数 $t, \ell, r$,表示操作的类型和范围 ($1 \le t \le 3$; $1 \le \ell \le r \le n$)。

输出格式

对于每个类型为 $3$ 的操作,输出一行,包含一个整数,即查询的答案。

样例

样例输入 1

10 10
0011101100
2 5 9
3 2 5
1 1 10
1 1 5
3 4 6
1 2 5
2 4 9
3 5 10
3 2 7
3 1 8

样例输出 1

2
1
3
3
4

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