ll@n,@m;
ll a[m]{},c[m]{},d[n]{},b[m][n];
ll z=0;
rep(i,n){
	rep(j,m){
		ll@r;
		if(r>=a[j]){
			if(r>a[j]){
				a[j]=r;
				rrep(k,c[j]){
					z-=!--d[b[j][k]];
				}
				c[j]=0;
			}
			z+=!d[b[j][c[j]++]=i]++;
		}
	}
	wt(z);
}