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#include <stdio.h>
#include <stdlib.h>
#include <assert.h>

typedef struct _path_t {
    struct _path_t *prev;
    struct _path_t *next;
    int dest;
} path_t;

typedef struct _data_t {
    path_t *frst;
    path_t *last;
    int len;
    int visited;
} data_t;

data_t data[200001];
path_t path[400000];
path_t *free_path;
int result[200000];
int respos = 0;

void path_add(int a, int b) {
    if(a != b) {
        free_path->prev = (data+a)->last;
        free_path->dest = b;
        if((data+a)->last) {
            (data+a)->last->next = free_path;
        } else {
            (data+a)->frst = free_path;
        }
        (data+a)->last = free_path;
        (data+a)->len++;
        free_path++;

        free_path->prev = (data+b)->last;
        free_path->dest = a;
        if((data+b)->last) {
            (data+b)->last->next = free_path;
        } else {
            (data+b)->frst = free_path;
        }
        (data+b)->last = free_path;
        (data+b)->len++;
        free_path++;
    }
}

void city_rem(int x, int d);

void path_rem(int a, int b, int d) {
    path_t *p;
    int done = 0;
    p = (data+a)->frst;
    while(!done && p) {
        if(p->dest == b) {
            if((data+a)->frst == p) {
                (data+a)->frst = p->next;
            }
            if((data+a)->last == p) {
                (data+a)->last = p->prev;
            }
            if(p->prev) {
                p->prev->next = p->next;
            }
            if(p->next) {
                p->next->prev = p->prev;
            }
            (data+a)->len--;
            if((data+a)->len && (data+a)->len < d) {
                city_rem(a, d);
            }
            done = 1;
        }
        p = p->next;
    }
}

void city_rem(int x, int d) {
//    printf("removing city # %d\n", x);
    path_t *p;
    (data+x)->len = 0;
    p = (data+x)->frst;
    while(p) {
        if((data+p->dest)->len) {
            path_rem(p->dest, x, d);
        }
        p = p->next;
    }
}

void path_print(int n) {
    int i;
    path_t *p;
    for(i=1; i<=n; i++) {
        if((data+i)->len) {
            printf("%d [%d]: ", i, (data+i)->len);
            p = (data+i)->frst;
            while(p) {
                printf("%d ", p->dest);
                p = p->next;
            }
            printf("\n");
        }
    }
}

int count(int a) {
    path_t *p;
    int res = 0;
    if(!(data+a)->visited && (data+a)->len) {
        (data+a)->visited = 1;
        p=(data+a)->frst;
        while(p) {
            res += count(p->dest);
            p = p->next;
        }
        res++;
    }
    return res;
}

void get(int a) {
    path_t *p;
    if((data+a)->visited) {
        (data+a)->visited = 0;
        (*(result+respos)) = a;
        respos++;
        p=(data+a)->frst;
        while(p) {
            get(p->dest);
            p = p->next;
        }
    }
}
       
int cmp (const void * a, const void * b) {
  return ( *(int*)a - *(int*)b );
}
       

int main() {
    int n, m, d, a, b, i, more, max, maxi, c;
    free_path = path;
    scanf("%d %d %d", &n, &m, &d);
    for(i=0; i<m; i++) {
        scanf("%d %d", &a, &b);
        path_add(a, b);
    }
    more = 1;
    while(more) {
        more = 0;
        for(i=1; i<=n; i++) {
            if((data+i)->len && (data+i)->len < d) {
                city_rem(i, d);
                more = 1;
            }
        }
    }
//    path_print(n);
    max = 0;
    for(i=1; i<=n; i++) {
        if(!(data+i)->visited && (data+i)->len) {
            c = count(i);
            if(max < c) {
                max = c;
                maxi = i;
            }
        }
    }
    if(max) {
        get(maxi);
        qsort(result, max, sizeof(int), cmp);
        printf("%d\n", max);
        for(i=0; i<max; i++) {
            printf("%d ", *(result+i));
        }
        printf("\n");
        
    } else {
        printf("NIE\n");
    }
    return 0;
}