Some algorithm problem solve

q1.cpp

#include <iostream>
#include <vector>

using namespace std;

void peak(vector<vector<int>> &table, int row, int col) {
  for (int i = 0; i < row; ++i) {
    for (int j = 0; j < col; ++j) {
      cout << table[i][j] << " ";
    }
    cout << endl;
  }
}

//solve position -1
int solver(vector<vector<int>> &table, int n, int k) {
  if (table[n][k] != -1) {
    return table[n][k];
  } else {
    if (k > n*(n-1)/2) {
      table[n][k] = 0;
      return 0;
    } else {
      int sum = 0;
      //cout << "process: (" << n << "," << k << ")" << endl;
      // pos is the position that ith number place
      for (int pos = 1; pos <= n; ++pos) {
        if (n-pos > k) {
          // if i-pos > j => place ith in pos will introduce too man inversion
          continue;
        } else {
          //cout << "pos: " << pos << " remainInversion: " << j-(i-pos) << endl;
          int remainInversion = k-(n-pos); // remain number of Inversion
          sum += solver(table, n-1, remainInversion);
        }
      }
      table[n][k] = sum;
      return sum;
    }
  }
}

int solve(int n, int k) {
  // prepare table
  vector<vector<int>> table(n+1, vector<int>(k+1, -1));
  for (int i = 1; i < n+1; ++i) {
    table[i][0] = 1;
  }

  int ans = solver(table, n, k);
  return ans;
}

int main(int argc, char *argv[])
{
  int n, k;
  cin >> n >> k;
  cout << solve(n, k) << endl;
  return 0;
}

q2.cpp

#include <iostream>
#include <vector>

using namespace std;

void printVec(vector<pair<unsigned int, unsigned int>> &v) {
  cout << "peak: ";
  for (auto i: v) {
    cout << "(" << i.first << "," << i.second << ") ";
  }
  cout << endl;
}

int query(vector<pair<unsigned int, unsigned int>> &peak, unsigned int idx)
{
  for (auto iter = peak.begin(); iter != peak.end(); iter++) {
    if (iter->first >= idx) {
      return iter->second;
    }
  }
}

void add(vector<pair<unsigned int, unsigned int>> &peak, unsigned int length,  int insert) {
  // update peak list
  while (peak.size()) {
    if (peak.back().second < insert) {
      peak.pop_back();
    } else {
      break;
    }
  }
  peak.push_back(pair<int, int>(length, insert));
}

int main() {
  int m;
  char ch[2];
  unsigned int mod = 0;
  unsigned int lastQuery = 0;
  unsigned int length = 0;
  vector<pair<unsigned int, unsigned int>> peak;

  cin >> m >> mod;
  while (m--) {
    int x;
    cin >> ch >> x;
    if (ch[0] == 'I')
    {
      int insert = (x+lastQuery) % mod;
      add(peak, length, insert);
      length++;
      //printVec(peak);
    } else {
      lastQuery = query(peak, length-x);
      cout << lastQuery << endl;
    }
  }
  return 0;
}