#include <cstdio>
#include <unistd.h>
#include <cassert>
#include <string>
#include<bits/stdc++.h>
using namespace std;
using ll = long long;
using ld = long double;
using str = string;
using pi = pair<int, int>;
using pl = pair<ll, ll>;
using pd = pair<ld, ld>;
#define mp make_pair
#define ff first
#define ss second
#define ar array
template<class T> using V = vector<T>;
using vi = V<int>;
using vb = V<bool>;
using vl = V<ll>;
using vd = V<ld>;
using vs = V<str>;
using vpi = V<pi>;
using vpl = V<pl>;
using vpd = V<pd>;
#define sz(x) (int)((x).size())
#define bg(x) begin(x)
#define all(x) bg(x), end(x)
#define rall(x) (x).rbegin(), (x).rend()
#define sor(x) sort(all(x))
#define rsz resize
#define ins insert
#define pb push_back
#define eb emplace_back
#define ft front()
#define bk back()
#define lb lower_bound
#define ub upper_bound
#define FOR(i, a, b) for(int i = (a); i < (b); ++i)
#define F0R(i, a) FOR(i, 0, a)
#define ROF(i, a, b) for(int i = (b) - 1; i >= (a); --i)
#define R0F(i, a) ROF(i, 0, a)
#define rep(a) F0R(_, a)
#define trav(a, x) for(auto& a : x)
template<class T> bool ckmin(T& a, const T& b) { return (b < a ? a = b, 1 : 0); }
template<class T> bool ckmax(T& a, const T& b) { return (b > a ? a = b, 1 : 0); }
const int dir[] = {0, -1, 0, 1, 0};
ll count_rectangles(V<vi> a) {
int M = sz(a.bk);
ll ans = 0;
vi LH(M, -1), RH(M, -1);
F0R(l, M) {
if(min(a[0][l], a[2][l]) <= a[1][l]) {
continue;
}
int r = l;
while(r + 1 < M && min(a[0][r + 1], a[2][r + 1]) > a[1][r + 1]) ++r;
vi q;
FOR(i, l, r + 1) {
while(sz(q) && a[1][q.bk] < a[1][i]) q.pop_back();
LH[i] = (!sz(q) ? -1 : q.bk);
q.pb(i);
}
q.clear();
ROF(i, r + 1, l) {
while(sz(q) && a[1][q.bk] < a[1][i]) q.pop_back();
RH[i] = (!sz(q) ? -1 : q.bk);
q.pb(i);
}
FOR(i, l, r + 1) {
if(LH[i] != -1 && i - LH[i] > 1) ++ans;
if(RH[i] != -1 && RH[i] - i > 1 && a[1][RH[i]] != a[1][i]) ++ans;
}
l = r;
}
return ans;
}
/*
using namespace std;
class InputReader {
private:
static const int SIZE = 4096;
int inputFileDescriptor;
char buf[SIZE];
int curChar;
int numChars;
public:
inline InputReader(int _inputFileDescriptor):
inputFileDescriptor(_inputFileDescriptor),
curChar(0),
numChars(0) {
}
inline void close() {
::close(inputFileDescriptor);
}
inline char read() {
assert(numChars != -1);
if (curChar >= numChars) {
curChar = 0;
numChars = ::read(inputFileDescriptor, buf, SIZE);
if (numChars == -1)
return -1;
}
return buf[curChar++];
}
inline int readInt() {
int c = eatWhite();
int sgn = 1;
if (c == '-') {
sgn = -1;
c = read();
}
int res = 0;
do {
assert(c >= '0' && c <= '9');
res *= 10;
res += c - '0';
c = read();
} while (!isSpaceChar(c));
return res * sgn;
}
inline string readString() {
char c = eatWhite();
string res;
do {
res += c;
c = read();
} while (!isSpaceChar(c));
return res;
}
inline string readLine() {
string res;
while (true) {
char c = read();
if (c == '\n' || c == '\r' || c == -1)
break;
res += c;
}
return res;
}
inline char eatWhite() {
char c = read();
while (isSpaceChar(c))
c = read();
return c;
}
static inline bool isSpaceChar(char c) {
return c == ' ' || c == '\n' || c == '\r' || c == '\t' || c == -1;
}
};
int main() {
InputReader inputReader(STDIN_FILENO);
int n, m;
n = inputReader.readInt();
m = inputReader.readInt();
vector<vector<int>> a(n, vector<int>(m));
for (int i = 0; i < n; i++) {
for (int j = 0; j < m; j++) {
a[i][j] = inputReader.readInt();
}
}
inputReader.close();
long long result = count_rectangles(a);
printf("%lld\n", result);
fclose(stdout);
return 0;
}*/
