Problem: JATC loves Banh-mi (a Vietnamese food). His affection for Banh-mi is so much that he always has it for breakfast. This morning, as usual, he buys a Banh-mi and decides to enjoy it in a special way.

First, he splits the Banh-mi into n parts, places them on a row and numbers them from 1 through n. For each part i, he defines the deliciousness of the part as x_i ∈ \{0, 1\}. JATC's going to eat those parts one by one. At each step, he chooses arbitrary remaining part and eats it. Suppose that part is the i-th part then his enjoyment of the Banh-mi will increase by x_i and the deliciousness of all the remaining parts will also increase by x_i. The initial enjoyment of JATC is equal to 0.

For example, suppose the deliciousness of 3 parts are [0, 1, 0]. If JATC eats the second part then his enjoyment will become 1 and the deliciousness of remaining parts will become [1, \\_, 1]. Next, if he eats the first part then his enjoyment will become 2 and the remaining parts will become [\\_, \\_, 2]. After eating the last part, JATC's enjoyment will become 4.

However, JATC doesn't want to eat all the parts but to save some for later. He gives you q queries, each of them consisting of two integers l_i and r_i. For each query, you have to let him know what is the maximum enjoyment he can get if he eats all the parts with indices in the range [l_i, r_i] in some order.

All the queries are independent of each other. Since the answer to the query could be very large, print it modulo 10^9+7.

Input

The first line contains two integers n and q (1 ≤ n, q ≤ 100 000).

The second line contains a string of n characters, each character is either '0' or '1'. The i-th character defines the deliciousness of the i-th part.

Each of the following q lines contains two integers l_i and r_i (1 ≤ l_i ≤ r_i ≤ n) — the segment of the corresponding query.

Output

Print q lines, where i-th of them contains a single integer — the answer to the i-th query modulo 10^9 + 7.

Examples

Input

4 2
1011
1 4
3 4


Output

14
3


Input

3 2
111
1 2
3 3


Output

3
1

Note

In the first example: 

  * For query 1: One of the best ways for JATC to eats those parts is in this order: 1, 4, 3, 2. 
  * For query 2: Both 3, 4 and 4, 3 ordering give the same answer. 



In the second example, any order of eating parts leads to the same answer.

Solution (in JAVA):

Solution:
import java.io.*;
import java.util.*;

public class Main {

    public static long MOD = 1000_000_007;

    public static void solve(FastIO io) {
        int n = io.nextInt();
        int q = io.nextInt();

        String parts = io.nextLine();
        int[] ones = new int[n+1];
        for(int i = 1; i <= n; ++i){
            if(parts.charAt(i-1) == '1')
                ones[i] = 1;
        }

        for(int i = 1; i <= n; ++i)
            ones[i] += ones[i-1];

        for(int i = 0, l, r; i < q; ++i){
            l = io.nextInt();
            r = io.nextInt();
            int oCnt = ones[r] - ones[l-1], zCnt = r-l+1 - oCnt;

            if(oCnt > 0) {
                long r1 = (binPow(2, oCnt, MOD) + MOD - 1)%MOD;
                long r2 = r1 * ((binPow(2, zCnt, MOD) + MOD - 1)%MOD) %MOD;

                io.println((r1 + (zCnt > 0 ? r2 : 0))%MOD);
                continue;
            }
            io.println(0);
        }
    }

    public static long binPow(long a, long b, long m){
        a %= m;
        long res = 1;
        while (b > 0) {
            if ((b & 1) != 0)
                res = res * a % m;
            a = a * a % m;
            b >>= 1;
        }
        return res;
    }

    public static class FastIO {
        private InputStream reader;
        private PrintWriter writer;

        private byte[] buf = new byte[1024];
        private int curChar;
        private int numChars;

        public FastIO(InputStream r, OutputStream w) {
            reader = r;
            writer = new PrintWriter(new BufferedWriter(new OutputStreamWriter(w)));
        }

        public int read() {
            if (numChars == -1)
                throw new InputMismatchException();
            if (curChar >= numChars) {
                curChar = 0;
                try {
                    numChars = reader.read(buf);
                } catch (IOException e) {
                    throw new InputMismatchException();
                }
                if (numChars <= 0)
                    return -1;
            }
            return buf[curChar++];
        }

        public String nextLine() {
            int c = read();
            while (isSpaceChar(c))
                c = read();
            StringBuilder res = new StringBuilder();
            do {
                res.appendCodePoint(c);
                c = read();
            } while (!isEndOfLine(c));
            return res.toString();
        }

        public String nextString() {
            int c = read();
            while (isSpaceChar(c))
                c = read();
            StringBuilder res = new StringBuilder();
            do {
                res.appendCodePoint(c);
                c = read();
            } while (!isSpaceChar(c));
            return res.toString();
        }

        public long nextLong() {
            int c = read();
            while (isSpaceChar(c))
                c = read();
            int sgn = 1;
            if (c == '-') {
                sgn = -1;
                c = read();
            }
            long res = 0;
            do {
                if (c < '0' || c > '9')
                    throw new InputMismatchException();
                res *= 10;
                res += c - '0';
                c = read();
            } while (!isSpaceChar(c));
            return res * sgn;
        }

        public int nextInt() {
            int c = read();
            while (isSpaceChar(c))
                c = read();
            int sgn = 1;
            if (c == '-') {
                sgn = -1;
                c = read();
            }
            int res = 0;
            do {
                if (c < '0' || c > '9')
                    throw new InputMismatchException();
                res *= 10;
                res += c - '0';
                c = read();
            } while (!isSpaceChar(c));
            return res * sgn;
        }

        public int[] nextIntArray(int n) {
            return nextIntArray(n, 0);
        }

        public int[] nextIntArray(int n, int off) {
            int[] arr = new int[n + off];
            for (int i = 0; i < n; i++) {
                arr[i + off] = nextInt();
            }
            return arr;
        }

        public long[] nextLongArray(int n) {
            return nextLongArray(n, 0);
        }

        public long[] nextLongArray(int n, int off) {
            long[] arr = new long[n + off];
            for (int i = 0; i < n; i++) {
                arr[i + off] = nextLong();
            }
            return arr;
        }

        private boolean isSpaceChar(int c) {
            return c == ' ' || c == '\n' || c == '\r' || c == '\t' || c == -1;
        }

        private boolean isEndOfLine(int c) {
            return c == '\n' || c == '\r' || c == -1;
        }

        public void print(Object... objects) {
            for (int i = 0; i < objects.length; i++) {
                if (i != 0) {
                    writer.print(' ');
                }
                writer.print(objects[i]);
            }
        }

        public void println(Object... objects) {
            print(objects);
            writer.println();
        }

        public void printArray(int[] arr) {
            for (int i = 0; i < arr.length; i++) {
                if (i != 0) {
                    writer.print(' ');
                }
                writer.print(arr[i]);
            }
        }

        public void printArray(long[] arr) {
            for (int i = 0; i < arr.length; i++) {
                if (i != 0) {
                    writer.print(' ');
                }
                writer.print(arr[i]);
            }
        }

        public void printlnArray(int[] arr) {
            printArray(arr);
            writer.println();
        }

        public void printlnArray(long[] arr) {
            printArray(arr);
            writer.println();
        }

        public void printf(String format, Object... args) {
            print(String.format(format, args));
        }

        public void flush() {
            writer.flush();
        }
    }

    public static void main(String[] args) throws FileNotFoundException {
        FastIO io = new FastIO(System.in, System.out);
        solve(io);
        io.flush();
    }
}