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#include <iostream>
#include <cstdio>
#include <string>
#include <sstream> 
#include <vector>
#include <set>
#include <map>
#include <queue>
#include <stack>
#include <cmath>
#include <algorithm>
#include <cstring>
#include <ctime>
#include <cassert>

#include "dzialka.h"
#include "message.h"

using namespace std;
#define pb push_back
#define mp make_pair
#define pii pair<int,int>
#define fi first
#define se second
#define vi vector<int>
#define vpii vector<pii>
#define SZ(x) ((int)(x.size()))
#define DBG cerr << "debug here" << endl;
#define DBGV(vari) cerr << #vari<< " = "<< (vari) <<endl;

using ll = long long;
using ull = long long;

const int INF = 1e9;

const int MASTER = 0;
const int N = 75000 + 10;
const int M = N;

const int MAXL = 75000/100 + 10;
//const int MAXL = 100;
bool a[MAXL][M];

int sum[M];
int sumGood[M];

int up[M];
int upGood[M];

int tmp[M];

const int CHUNK = 10000;

ull countSubgrids(ull x, ull y) {
    return x*(x+1)/2 * y;
}

struct Entry {
    ull x;
    ull height;
    ull deltaY;
    ull accX;
    Entry() {}
    Entry(ull x_, ull height_, ull deltaY_, ull accX_) : x(x_), height(height_), deltaY(deltaY_), accX(accX_) {
    }
};
int main()
{
    ios_base::sync_with_stdio(0);

    const int id = MyNodeId();
    const int n = GetFieldHeight();
    const int m = GetFieldWidth();
    const int k = min(n, NumberOfNodes());

    //don't need such instances
    if (id >= k) return 0;

    const int blockLen = ceil(n / (double)k);
    const ll A = id*blockLen;
    const ll B = min(n-1, (id+1)*blockLen-1);
    const ll L = B-A+1;

    /* reading values in my range */
    for (int i = A; i <= B; ++i) {
        for (int j = 0; j < m; ++j) {
            a[i-A][j] = IsUsableCell(i, j) == 1;
        }
    }


    /* initialize sum[m] and sumGood[m] arrays */
    for (int j = 0; j < m; ++j) {
        for (int i = L-1; i >= 0 and a[i][j]; --i) {
            sum[j]++;
        }
        sumGood[j] = sum[j] == L;
    }

    // initializing upGood[m] array
    for (int j = 0; j < m; ++j) {
        upGood[j] = true;
    }

    // precomputing prefix sums in parallel
    int step = 1;
    int wantedPrefSz = blockLen;
    while (id+step < k or id-step >= 0) {
        if (id+step < k) {
            int recipient = id+step;
            for (int j = 0; j < m; ++j) {
                if (j > 0 and j % CHUNK == 0) {
                    Send(recipient);
                }
                PutInt(recipient, sum[j]);
            }
            Send(recipient);
        }
        if (id-step >= 0) {
            int sender = id-step;
            int cnt = 0;
            for (int j = 0; j < m; ++j) {
                if (j % CHUNK == 0) {
                    Receive(sender);
                }
                tmp[j] = GetInt(sender);
            }
                
            // merge tmp array into up array, and up array into sum array
            for (int j = 0; j < m; ++j) {
                if (upGood[j]) {
                    up[j] += tmp[j];
                    if (up[j] < wantedPrefSz) {
                        upGood[j] = false;
                    }
                    if (sumGood[j]) {
                        sum[j] += tmp[j];
                    }
                }
            }
        }
        step *= 2;
        wantedPrefSz += step*blockLen;
    }

    // computing local result
    ull result = 0;
    for (int i = 0; i < L; ++i) {
        ull rowResult = 0;
        for (int j = 0; j < m; ++j) {
            if (a[i][j]) {
                if (i == 0) {
                    tmp[j] = up[j] + 1;
                } else {
                    tmp[j]++;
                }
            } else {
                tmp[j] = 0;
            }
        }
        stack<Entry> q;
        for (int j = 0; j < m; ++j) {
            int h = tmp[j];
            ull accX = 0;
            while (!q.empty() and q.top().height > h) {
                ull a = j - q.top().x;
                ull b = q.top().deltaY;
                accX = max(accX, a+q.top().accX);
                rowResult += countSubgrids(a, b);
                rowResult += (q.top().accX * a) * b;
                q.pop();
            }
            ull deltaY = q.empty() ? h : h-q.top().height;
            if (deltaY > 0) {
                q.push(Entry(j, h, deltaY, accX));
            }
        }
        while (!q.empty()) {
            ull a = m - q.top().x;
            ull b = q.top().deltaY;
            rowResult += countSubgrids(a, b);
            rowResult += (q.top().accX * a) * b;
            q.pop();
        }
        result += rowResult;
    }
    
    if (id != MASTER) {
        PutLL(MASTER, result);
        Send(MASTER);
    } else {
        for (int sender = 0; sender < k; ++sender) {
            if (sender == MASTER) continue;
            Receive(sender);
            ll subresult = GetLL(sender);
            result += subresult;
        }
        cout << result << endl;
    }
    return 0;
}