#include using namespace std;

int main() { long long H, W, x; cin >> H >> W >> x;

long long cnt = 0;

for (long long r = 1; r <= H; r++) {
    for (long long c = 1; c <= W; c++) {
        long long right = x + r - c;
        long long left = r * r + c * c;
        long long right2 = right * right;

        if (left <= right2) {
            cnt++;
        }
    }
}

cout << cnt << endl;
return 0;

}

#include <iostream>
using namespace std;

int main() {
    int t;
    cin >> t;

    while (t--) {
        long long a;
        cin >> a;

        long long left = 1, right = 100, ans = -1;

        while (left <= right) {
            long long mid = (left + right) / 2;
            long long val = mid * mid * mid * mid;

            if (val == a) {
                ans = mid;
                break;
            } else if (val < a) {
                left = mid + 1;
            } else {
                right = mid - 1;
            }
        }

        cout << ans << endl;
    }

    return 0;
}

#include<bits/stdc++.h> using namespace std; int main(){ long long n,sum=0,max1=0,x; cin>>n; for(int i=1;i<=n;i++){ cin>>x; while(x){ sum+=x%10; x/=10; } max1=max(max1,sum); sum=0; } cout<<max1; return 0; }

#include<bits/stdc++.h> using namespace std; int main() { int n,m,a=1; cin>>n>>m; for(int i=1;i<=n;i++) { a=i; for(int j=1;j<=m;j++) { cout<<a<<" "; a+=i; } cout<<endl; } return 0; }