#include<bits/stdc++.h>
using namespace std;
int n , m , ans , k;
int a[505][505];
int b[505][505];
int main(){
	cin >> n >> m >> k;
	for(int i=1;i<=n;i++){
		for(int j=1;j<=m;j++){
			cin >> a[i][j];
			b[i][j] = b[i-1][j] + b[i][j-1] - b[i-1][j-1] + a[i][j];
		}
	}
	for(int i=1;i<=n;i++){
		for(int j=1;j<=m;j++){
			for(int i2=i;i2<=n;i2++){
				for(int j2=j;j2<=m;j2++){
					if(b[i2][j2]-b[i-1][j2]-b[i2][j-1]+b[i-1][j-1]<=k){
						ans++;
					}
				}
			}
		}
	}
	cout << ans;
	return 0;
}