#include <stdio.h>

int main() {
    freopen("graf.in", "r", stdin);
    freopen("graf.out", "w", stdout);

    int n, m, x, y;

    scanf("%d %d", &n, &m);

    int a[n+1][n+1];

    for (int i = 1; i <= n; i++) {
        for (int j = 1; j <= n; j++) {
            a[i][j] = 0;
        }
    }

    for (int i = 0; i < m; i++) {
        scanf("%d %d", &x, &y);

        a[x][y] = a[y][x] = 1;
    }

    int nrMuchii = 0;

    for (int i = 1; i <= n; i++) {
        for (int j = 1; j <= n; j++) {
            printf("%d ", a[i][j]);
        }

        printf("\n");
    }

    for (int i = 1; i <= n; i++) {
        for (int j = i+1; j <= n; j++) {
            if (a[i][j] == 0) {
                nrMuchii++;

                printf("%d %d\n", i, j);
            }
        }
    }

    printf("%d", nrMuchii);

}