#include <bits/stdc++.h>
using namespace std;
using ll = long long;
const int maxn = (int)1e3+5;
int n, m;
int a[maxn][maxn];
namespace sub1 {
ll ans = 0;
int prv = -1;
bool check () {
return (n <= 50 && m <= 50);
}
void solve () {
for (int top = 1; top <= n; top++) {
for (int bot = top; bot <= n; bot++) {
for (int lft = 1; lft <= m; lft++) {
prv = -1;
for (int rht = lft; rht <= m; rht++) {
bool ok = 1;
for (int s = top; s <= bot; s++) {
if (a[s][rht] != prv && prv != -1) {
ok = 0;
break;
}
else if (prv == -1) {
prv = a[s][rht];
}
}
ans += ok;
if (!ok) break;
}
}
}
}
cout << ans << "\n";
}
}
namespace sub2 {
ll ans = 0;
bitset<505> valid[505][505];
bool check () {
return (n <= 500 && m <= 500);
}
void solve () {
for (int col = 1; col <= m; col++) {
for (int top = 1; top <= n; top++) {
valid[col][top][top] = 1;
for (int bot = top+1; bot <= n; bot++) {
if (a[bot][col] != a[bot-1][col]) break;
valid[col][top][bot] = 1;
}
}
}
for (int top = 1; top <= n; top++) {
for (int bot = top; bot <= n; bot++) {
ll tmp = 0;
for (int rht = 1; rht <= m; rht++) {
if (!valid[rht][top][bot]) {
tmp = 0;
}
else if (valid[rht][top][bot] && rht > 1 && a[bot][rht] != a[bot][rht-1]) {
tmp = 1;
ans += tmp;
}
else {
tmp++;
ans += tmp;
}
}
}
}
cout << ans << "\n";
}
}
namespace sub3 {
stack<int> st;
int h[maxn][maxn];
int lft[maxn][maxn];
int rht[maxn][maxn];
ll ans = 0;
ll cal (int row, int l, int r) {
ll sum = 0;
st = stack<int>();
for (int i = l;i <= r; i++) {
while (st.size() && h[row][st.top()] >= h[row][i]) st.pop();
lft[row][i] = (st.size() ? st.top() + 1 : l);
st.push(i);
}
st = stack<int>();
for (int i = r;i >= l; i--) {
while (st.size() && h[row][st.top()] > h[row][i]) st.pop();
rht[row][i] = (st.size() ? st.top() - 1 : r);
st.push(i);
}
for (int i = l;i <= r; i++) {
sum += 1LL * (i-lft[row][i] + 1) * (rht[row][i] - i + 1) * h[row][i];
}
return sum;
}
void solve () {
for (int row = 1;row <= n; row++) {
for (int col = 1; col <= m; col++) {
if (a[row][col] != a[row-1][col]) {
h[row][col] = 1;
}
else {
h[row][col] = h[row-1][col] + 1;
}
}
}
for (int row = 1; row <= n; row++) {
int fst = 1;
for (int col = 2; col <= m; col++) {
if (a[row][fst] != a[row][col]) {
ans += cal(row, fst, col-1);
fst = col;
}
}
ans += cal(row, fst, m);
}
cout << ans << "\n";
}
}
void read_and_prep() {
cin >> n >> m;
for (int i = 1;i <= n; i++) {
for (int j = 1;j <= m; j++) cin >> a[i][j];
}
}
int main () {
ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
read_and_prep();
if (sub1::check()) sub1::solve();
else if (sub2::check()) sub2::solve();
else sub3::solve();
return 0;
}
