#include <bits/stdc++.h>
using namespace std;
#define sz(x) (int)(x.size())
#define all(x) begin(x), end(x)
using ll = long long;
const ll MOD = 3006703054056749;
const int ALPHA = 4;
const map<char, int> pos = {{'A', 0}, {'C', 1}, {'G', 2}, {'T', 3}};
void add(ll &x, ll v) {
if ((x += v) >= MOD) x -= MOD;
}
int main() {
ios::sync_with_stdio(0);
cin.tie(0); cout.tie(0);
random_device rd;
mt19937 gen(rd());
uniform_int_distribution<int> dist(1, 1e9);
int n, m, k;
cin >> n >> m >> k;
vector<string> s(n);
for (int i = 0; i < n; i++) {
cin >> s[i];
}
vector<ll> val(n);
ll tot = 0LL;
vector<vector<ll>> sum(m, vector<ll>(ALPHA, 0LL));
for (int i = 0; i < n; i++) {
val[i] = dist(gen);
add(tot, val[i]);
for (int j = 0; j < m; j++) {
add(sum[j][pos.at(s[i][j])], val[i]);
}
}
ll target = k * tot % MOD;
for (int i = 0; i < n; i++) {
ll curr = k * val[i] % MOD;
for (int j = 0; j < m; j++) {
ll diff = tot - sum[j][pos.at(s[i][j])];
if (diff < 0) diff += MOD;
add(curr, diff);
}
if (curr == target) {
cout << i + 1 << '\n';
}
}
return 0;
}
