#include<bits/stdc++.h>
using namespace std;
#define N 2010
typedef long long ll;
int n,m;
ll ans;
char a[N][N],_a[N][N];
void calc(int l1,int r1,int l2,int r2,char a[][N]){
	static int L[N],R[N],D[N][N],U[N][N],slU[N][N],slD[N][N],srU[N][N],srD[N][N];
	int mid=(l2+r2)>>1;
	for(int i=l1;i<=r1;++i){
		L[i]=R[i]=0;
		while(mid-L[i]>=l2&&a[i][mid]==a[i][mid-L[i]])++L[i];
		while(mid+R[i]+1<=r2&&a[i][mid+1]==a[i][mid+R[i]+1])++R[i];
	}
	for(int i=r1;i>=l1;--i){
		for(int j=l2;j<=r2;++j){
			D[i][j]=(i<r1&&a[i][j]==a[i+1][j])?D[i+1][j]:i;
		}
	}
	for(int i=l1;i<=r1;++i){
		for(int j=l2;j<=r2;++j){
			U[i][j]=(i>l1&&a[i][j]==a[i-1][j])?U[i-1][j]:i;
		}
	}
	for(int i=l1;i<=r1;++i){
		for(int j=l1;j<=r1;++j){
			slU[i][j]=slD[i][j]=srU[i][j]=srD[i][j]=0;
		}
	}
	for(int i=l1;i<=r1;++i){
		for(int j=mid;j>=mid-L[i]+1;--j){
			++slU[i][U[i][j]],++slD[i][D[i][j]];
		}
		for(int j=mid+1;j<=mid+R[i];++j){
			++srU[i][U[i][j]],++srD[i][D[i][j]];
		}
		for(int j=l1+1;j<=i;++j){
			slU[i][j]+=slU[i][j-1];
			srU[i][j]+=srU[i][j-1];
		}
		for(int j=r1-1;j>=i;--j){
			slD[i][j]+=slD[i][j+1];
			srD[i][j]+=srD[i][j+1];
		}
	}
	for(int i=l1;i<=r1;++i){
		for(int j=i+1;j<=r1;++j){
			if(a[i][mid]==a[j][mid]&&a[i][mid]==a[i][mid+1]&&a[i][mid+1]==a[j][mid+1]){
				int lw,rw;
				if(L[i]<L[j])lw=slD[i][j];
				else lw=slU[j][i];
				if(R[i]<R[j])rw=srD[i][j];
				else rw=srU[j][i];
				ans+=lw*rw;
			}
		}
	}
}
void Solve(int l1,int r1,int l2,int r2){
	if(l1>=r1||l2>=r2)return;
	if(r1-l1<r2-l2){
		int mid=(l2+r2)>>1;
		calc(l1,r1,l2,r2,a);
		Solve(l1,r1,l2,mid);
		Solve(l1,r1,mid+1,r2);
	}
	else{
		int mid=(l1+r1)>>1;
		calc(l2,r2,l1,r1,_a);
		Solve(l1,mid,l2,r2);
		Solve(mid+1,r1,l2,r2);
	}
}
int main(){
	ios::sync_with_stdio(false);
	cin.tie(0);
	cin>>n>>m;
	for(int i=1;i<=n;++i){
		cin>>(a[i]+1);
		for(int j=1;j<=m;++j){
			_a[j][i]=a[i][j];
		}
	}
	Solve(1,n,1,m);
	cout<<ans<<'\n';
	return 0;
}