677.cpp

#include <bits/stdc++.h>
using namespace std;
int a[20][20];
bool visit[15];
vector<int> v;
int N, R, flag;
void call(int r) {
    int i, j, k;
    if (v.size() == N + 1) {
        flag = 1;
        printf("(");
        for (i = 0; i < v.size(); i++) {
            if (i != 0) printf(",");
            printf("%d", v[i] + 1);
        }
        printf(")\n");
        return;
    }
    for (i = 0; i < R; i++) {
        if (a[r][i] == 1 && visit[i] == 0) {
            v.push_back(i);
            visit[i] = 1;
            call(i);
            visit[i] = 0;
            v.pop_back();
        }
    }
    return;
}

int main() {
    int tc, n, i, j, k;
    int t = 0;
    while (scanf("%d", &tc) == 1) {
        if (tc == -9999) {
            scanf("%d%d", &R, &N);
        } else {
            R = tc;
            scanf("%d", &N);
        }
        for (i = 0; i < R; i++)
            for (j = 0; j < R; j++) scanf("%d", &a[i][j]);
        memset(visit, 0, sizeof(visit));
        if (t != 0) puts("");
        t++;
        v.clear();
        v.push_back(0);
        visit[0] = 1;
        flag = 0;
        call(0);
        if (flag == 0) printf("no walk of length %d\n", N);
    }
    return 0;
}