#D9438. New Year and Old Subsequence

    ID: 7850 Type: Default 3000ms 256MiB

New Year and Old Subsequence

New Year and Old Subsequence

A string t is called nice if a string "2017" occurs in t as a subsequence but a string "2016" doesn't occur in t as a subsequence. For example, strings "203434107" and "9220617" are nice, while strings "20016", "1234" and "20167" aren't nice.

The ugliness of a string is the minimum possible number of characters to remove, in order to obtain a nice string. If it's impossible to make a string nice by removing characters, its ugliness is - 1.

Limak has a string s of length n, with characters indexed 1 through n. He asks you q queries. In the i-th query you should compute and print the ugliness of a substring (continuous subsequence) of s starting at the index ai and ending at the index bi (inclusive).

Input

The first line of the input contains two integers n and q (4 ≤ n ≤ 200 000, 1 ≤ q ≤ 200 000) — the length of the string s and the number of queries respectively.

The second line contains a string s of length n. Every character is one of digits '0'–'9'.

The i-th of next q lines contains two integers ai and bi (1 ≤ ai ≤ bi ≤ n), describing a substring in the i-th query.

Output

For each query print the ugliness of the given substring.

Examples

Input

8 3 20166766 1 8 1 7 2 8

Output

4 3 -1

Input

15 5 012016662091670 3 4 1 14 4 15 1 13 10 15

Output

-1 2 1 -1 -1

Input

4 2 1234 2 4 1 2

Output

-1 -1

Note

In the first sample:

  • In the first query, ugliness("20166766") = 4 because all four sixes must be removed.
  • In the second query, ugliness("2016676") = 3 because all three sixes must be removed.
  • In the third query, ugliness("0166766") = - 1 because it's impossible to remove some digits to get a nice string.

In the second sample:

  • In the second query, ugliness("01201666209167") = 2. It's optimal to remove the first digit '2' and the last digit '6', what gives a string "010166620917", which is nice.
  • In the third query, ugliness("016662091670") = 1. It's optimal to remove the last digit '6', what gives a nice string "01666209170".

inputFormat

Input

The first line of the input contains two integers n and q (4 ≤ n ≤ 200 000, 1 ≤ q ≤ 200 000) — the length of the string s and the number of queries respectively.

The second line contains a string s of length n. Every character is one of digits '0'–'9'.

The i-th of next q lines contains two integers ai and bi (1 ≤ ai ≤ bi ≤ n), describing a substring in the i-th query.

outputFormat

Output

For each query print the ugliness of the given substring.

Examples

Input

8 3 20166766 1 8 1 7 2 8

Output

4 3 -1

Input

15 5 012016662091670 3 4 1 14 4 15 1 13 10 15

Output

-1 2 1 -1 -1

Input

4 2 1234 2 4 1 2

Output

-1 -1

Note

In the first sample:

  • In the first query, ugliness("20166766") = 4 because all four sixes must be removed.
  • In the second query, ugliness("2016676") = 3 because all three sixes must be removed.
  • In the third query, ugliness("0166766") = - 1 because it's impossible to remove some digits to get a nice string.

In the second sample:

  • In the second query, ugliness("01201666209167") = 2. It's optimal to remove the first digit '2' and the last digit '6', what gives a string "010166620917", which is nice.
  • In the third query, ugliness("016662091670") = 1. It's optimal to remove the last digit '6', what gives a nice string "01666209170".

样例

15 5
012016662091670
3 4
1 14
4 15
1 13
10 15
-1

2 1 -1 -1

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