#include <iostream>
#include <cstdio>
#include <climits>
#include <algorithm>
using namespace std;
 
int a[105][105];
 
int main() {
	int r, c, mi, ma, cnt;
	scanf("%d%d", &r, &c);
	for(int i=0; i<r; i++) for(int j=0; j<c; j++) scanf("%d", &a[i][j]);
	for(int i=0; i<r; i++) {
		mi=INT_MAX, ma=INT_MIN;
		for(int j=0; j<c; j++) {
			mi=min(mi, a[i][j]);
		}
		for(int j=0; j<c; j++) {
			if(a[i][j]==mi) {
				cnt=0;
				for(int k=0; k<r; k++) if(mi>=a[k][j]) cnt++;
				if(cnt==r) {printf("%d", mi); return 0;}
			}
		}
	}
	printf("GUESS");
	return 0;
}

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MiAyCjEwIDEwCjEwIDEwCg==

2 2
10 10
10 10