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#include <iostream>
#include <vector>
#include <algorithm>
#include <string>
#include <map>
#include <set>
#include <chrono>
#include <functional>
#include <cstdlib>
using namespace std;

const unsigned long long P = 1000000007;
const unsigned long long MAX_N = 200001;

inline char getLetterOfForbiddenLetterSequence1(int position)
{
  if (position % 2 == 0)
    return 'C';
  else
    return 'Z';
}

inline char getLetterOfForbiddenLetterSequence2(int position)
{
  if (position % 2 == 0)
    return 'Z';
  else
    return 'C';
}

struct SequenceDescription
{
  int size = 0;
  int redCount = 0;
  int blueCount = 0;
  int greenCount = 0;
  int numberMatches1 = 0;
  int numberMatches2 = 0;
  void reportTermion(char termion, int position)
  {
    ++size;
    if (termion == 'C')
      ++redCount;
    if (termion == 'Z')
      ++greenCount;
    if (termion == 'N')
      ++blueCount;
    if (getLetterOfForbiddenLetterSequence1(position) == termion)
      ++numberMatches1;
    if (getLetterOfForbiddenLetterSequence2(position) == termion)
      ++numberMatches2;
  }
  void unreportTermion(char termion, int position)
  {
    --size;
    if (termion == 'C')
      --redCount;
    if (termion == 'Z')
      --greenCount;
    if (termion == 'N')
      --blueCount;
    if (getLetterOfForbiddenLetterSequence1(position) == termion)
      --numberMatches1;
    if (getLetterOfForbiddenLetterSequence2(position) == termion)
      --numberMatches2;
  }
};

class Newton
{
  std::vector<unsigned long long> k0;
  std::vector<unsigned long long> k1;
  std::vector<unsigned long long> k2;
public:
  Newton():
    k0(MAX_N, 0),
    k1(MAX_N, 0),
    k2(MAX_N, 0)
  {
    k0[0] = 1;
    for (int i = 1; i < MAX_N; ++i)
    {
      k0[i] = (k0[i-1] + k2[i-1]) % P;
      k1[i] = (k0[i-1] + k1[i-1]) % P;
      k2[i] = (k1[i-1] + k2[i-1]) % P;
    }
  }
  unsigned long long getValue(int n, int k)
  {
    if (k == 0)
      return k0[n];
    if (k == 1)
      return k1[n];
    return k2[n];
  }
};

unsigned long long getNumberOfCombinations(SequenceDescription & desc, Newton & newton)
{
  int diff = std::abs(desc.greenCount - desc.redCount);
  unsigned long long result = 0;
  for (int i = 0; i < 3; ++i)
  {
    int newDiff = diff + (desc.blueCount - 2*i);
    if (std::abs(newDiff) % 3 != 0)
      result = (result + newton.getValue(desc.blueCount, i)) % P;
  }
  if (desc.size % 2 == 1)
  {
    if (desc.numberMatches1 == (desc.greenCount + desc.redCount))
      result = (result + P - 1) % P;
    if (desc.numberMatches2 == (desc.greenCount + desc.redCount))
      result = (result + P - 1) % P;
  }
  return result;
}

int main()
{
  const clock_t begin_time = clock();
  ios::sync_with_stdio(false);
  Newton newton;
  int termionCount;
  std::cin >> termionCount;
  int changeCount;
  std::cin >> changeCount;
  std::string termions;
  std::cin >> termions;
  SequenceDescription desc;
  for (int i = 0; i < termions.size(); ++i)
  {
    desc.reportTermion(termions[i], i);
  }
  std::cout << getNumberOfCombinations(desc, newton) << "\n";
  for (int i = 0; i < changeCount; ++i)
  {
    int pos;
    std::cin >> pos;
    --pos;
    std::string singleTermion;
    std::cin >> singleTermion;
    desc.unreportTermion(termions[pos], pos);
    termions[pos] = singleTermion[0];
    desc.reportTermion(singleTermion[0], pos);
    unsigned long long numberOfCombinations = getNumberOfCombinations(desc, newton);
    std::cout << numberOfCombinations << "\n";
  }
  //std::cout << float(clock() - begin_time) / CLOCKS_PER_SEC << "\n";
  return 0;
};