#include<bits/stdc++.h>
using namespace std;
long long mod=1000000000000000003ll;
#define ull unsigned long long
ull seed=131313131;
ull ran(){
	seed^=seed<<13;
	seed^=seed>>7;
	seed^=seed<<17;
	return seed;
}
long long hx[100005];
char s[20000005];
long long tj[100005][26];
int main(){
	int n,m,k;
	scanf("%d%d%d",&n,&m,&k);
	long long zh=0;
	for(int i=1;i<=n;++i){
		hx[i]=ran()%mod;
		scanf("%s",s+(i-1)*m+1);
		for(int j=1;j<=m;++j){
			char ss=s[(i-1)*m+j];
			tj[j][ss-'A']=(tj[j][ss-'A']+hx[i])%mod;
		}
		zh=(zh+hx[i])%mod;
	}
	for(int i=1;i<=n;++i){
		long long he=0;
		for(int j=1;j<=m;++j){
			char ss=s[(i-1)*m+j];
			he=(he+tj[j][ss-'A']-hx[i]+mod)%mod;
		}
		if(he==(__int128)(zh-hx[i]+mod)*(m-k)%mod){
			printf("%d\n",i);
		}
	}
	return 0;
}