#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define pii pair<int,int>
#define fi first
#define in inline
#define se second
#define mp make_pair
#define pb push_back
const int N = 60,M = 410;

ll read(){
	ll x = 0,f = 1;char c = getchar();
	for(;c < '0' || c > '9';c = getchar())if(c == '-')f = -1;
	for(;c >= '0' && c <= '9';c = getchar())x = (x<<1) + (x<<3) + c-'0';
	return x * f;
}


int n,m,p;
int a[N][M],top[N];
bool v[N];

vector<pii>ans;
void prin(int x,int y){
	if(x == y)return;
	a[y][++top[y]] = a[x][top[x]],a[x][top[x]--] = 0;
	ans.pb({x,y});
}
//int del[N],cnt = 0;
int main(){
	freopen("2020ball.in","r",stdin);
	freopen("2020ball.out","w",stdout);
	n = read(),m = read();
	p = n + 1;
	for(int i = 1;i <= n;i++)
		for(int j = 1;j <= m;j++)a[i][j] = read(),top[i] = m;
//	for(int i = 1;i <= m;i++)del[++cnt] = n + 1;
	for(int i = 1;i < n;i++){
		for(int j = 1;j < p;j++){
			if(v[j])continue;
			int s = 0,mi = n + 1;
			for(int k = 1;k <= m;k++)if(a[j][k] == i)mi = min(mi,k),s++;
			if(!s)continue;
			int w = (j == p-1 ? j - 1 : j + 1);
			for(int k = 1;k <= s;k++)prin(w,p);
			for(int k = m;k >= 1;k--)
				if(a[j][k] != i)prin(j,p);
				else prin(j,w);
			for(int k = m;k > s;k--)prin(p,j);
			for(int k = 1;k <= s;k++)prin(w,j);
			for(int k = s;k >= 1;k--)prin(p,w);
//			cnt = m;
		}
		for(int j = p-1;j >= 1;j--){
			int s = 0;
			for(int k = m;k >= 1;k--){
				if(a[j][k] != i)break;
				prin(j,p),s++;
			}
			for(int k = 1;k <= s;k++)prin(p-1,j);
		}
		p = p - 1;
	}
//	printf("\n---------\n");
//	for(int i = 1;i <= n + 1;i++){
//		for(int j = 1;j <= m;j++)
//			printf("%d ",a[i][j]);
//		printf("\n----\n");
//	}
	printf("%d\n",(int)ans.size());
	for(auto x : ans)printf("%d %d\n",x.fi,x.se);

	return 0;

}