Lưu ý: Các code mẫu dưới đây chỉ mang tính tham khảo và có thể không AC được bài tập này

Code mẫu của flashmt

#include <iostream>
#include <algorithm>
#include <cstdio>
using namespace std;

int n,m,next[1000100],a[1000100],ans[1000100],lastPos[1000100];

int findNext(int x,int cur)
{
    if (x>=cur) return 0;
    if (a[next[x]] || ans[next[x]]) next[x]=findNext(next[x]+1,cur);
    return next[x];
}

int main()
{
    int test;
    cin >> test;
    while (test--)
    {
        int ok=1;
        cin >> n >> m;
        for (int i=1;i<=n;i++) lastPos[i]=1;
        for (int i=1;i<=m;i++) scanf("%d",&a[i]), next[i]=i;
        for (int i=1;i<=m && ok;i++)
            if (a[i])
            {
                int x=findNext(lastPos[a[i]],i);
                if (!x) ok=0;
                else ans[x]=a[i];
                lastPos[a[i]]=i;
            }
            else ans[i]=0;
        if (ok)
        {
            puts("YES");
            for (int i=1;i<=m;i++)
                if (!a[i]) printf("%d ",ans[i]);
            puts("");
        }
        else puts("NO");
    }
}

Code mẫu của ladpro98

#include <cstring>
#include <vector>
#include <list>
#include <map>
#include <set>
#include <queue>
#include <deque>
#include <stack>
#include <bitset>
#include <algorithm>
#include <functional>
#include <numeric>
#include <utility>
#include <sstream>
#include <iostream>
#include <iomanip>
#include <cstdio>
#include <cmath>
#include <climits>
#include <cstdlib>
#include <ctime>
#include <memory.h>
#include <cassert>
#include <climits>
#define FOR(i, a, b) for(int i = (a); i < (b); i++)
#define REP(i, a, b) for(int i = (a); i <=(b); i++)
#define FORD(i, a, b) for(int i = (a); i > (b); i--)
#define REPD(i, a, b) for(int i = (a); i >=(b); i--)
#define TR(it, a) for(typeof((a).begin()) it = (a).begin(); it != (a).end(); it++)
#define SZ(a) (int((a).size()))
#define ALL(a) (a).begin(), (a).end()
#define PB push_back
#define MP make_pair
#define LL long long
#define LD long double
#define II pair<int, int>
#define X first
#define Y second
#define VI vector<int>
const int N = 1000006;
using namespace std;
set<int> freeDays;
int n, m, ntest;
int last[N], ans[N], pos[N];

int main() {
    ios :: sync_with_stdio(0); cin.tie(0);
    cin >> ntest;
    while (ntest--) {
        cin >> n >> m;
        bool ok = 1; int lake, cnt = 0;
        freeDays.clear();
        FOR(i, 0, m) {
            cin >> lake;
            if (lake == 0) {
                freeDays.insert(i);
                pos[i] = cnt;
                ans[cnt++] = 0;
            }
            else {
                set<int> :: iterator it = freeDays.lower_bound(last[lake]);
                if (it == freeDays.end()) {
                    cout << "NO\n"; ok = 0; break;
                }
                last[lake] = i;
                ans[pos[*it]] = lake;
                freeDays.erase(it);
            }
        }
        if (ok) {
            cout << "YES\n";
            FOR(i, 0, cnt) cout << ans[i] << ' ';
            cout << '\n';
        }
        REP(i, 1, n) last[i] = 0;
    }
    return 0;
}

Code mẫu của RR

#include <sstream>
#include <iomanip>
#include <iostream>
#include <cstdio>
#include <cstring>
#include <cstdlib>
#include <cmath>
#include <algorithm>
#include <vector>
#include <set>
#include <map>
#include <stack>
#include <queue>
#include <string>
#include <deque>
#include <complex>

#define FOR(i,a,b) for(int i=(a),_b=(b); i<=_b; i++)
#define FORD(i,a,b) for(int i=(a),_b=(b); i>=_b; i--)
#define REP(i,a) for(int i=0,_a=(a); i<_a; i++)
#define FORN(i,a,b) for(int i=(a),_b=(b);i<_b;i++)
#define DOWN(i,a,b) for(int i=a,_b=(b);i>=_b;i--)
#define SET(a,v) memset(a,v,sizeof(a))
#define sqr(x) ((x)*(x))
#define ll long long
#define F first
#define S second
#define PB push_back
#define MP make_pair

#define DEBUG(x) cout << #x << " = "; cout << x << endl;
#define PR(a,n) cout << #a << " = "; FOR(_,1,n) cout << a[_] << ' '; cout << endl;
#define PR0(a,n) cout << #a << " = "; REP(_,n) cout << a[_] << ' '; cout << endl;
using namespace std;

//Buffer reading
int INP,AM,REACHEOF;
#define BUFSIZE (1<<12)
char BUF[BUFSIZE+1], *inp=BUF;
#define GETCHAR(INP) { \
    if(!*inp) { \
        if (REACHEOF) return 0;\
        memset(BUF,0,sizeof BUF);\
        int inpzzz = fread(BUF,1,BUFSIZE,stdin);\
        if (inpzzz != BUFSIZE) REACHEOF = true;\
        inp=BUF; \
    } \
    INP=*inp++; \
}
#define DIG(a) (((a)>='0')&&((a)<='9'))
#define GN(j) { \
    AM=0;\
    GETCHAR(INP); while(!DIG(INP) && INP!='-') GETCHAR(INP);\
    if (INP=='-') {AM=1;GETCHAR(INP);} \
    j=INP-'0'; GETCHAR(INP); \
    while(DIG(INP)){j=10*j+(INP-'0');GETCHAR(INP);} \
    if (AM) j=-j;\
}
//End of buffer reading

const long double PI = acos((long double) -1.0);

int n, m, a[1000111], b[1000111], res[1000111];
bool full[1000111];

int main() {
    int ntest; scanf("%d", &ntest);
    while (ntest--) {
        scanf("%d%d", &n, &m);
        FOR(i,1,n) full[i] = true;

        int nb = 0;
        FOR(i,1,m) {
            scanf("%d", &a[i]);
            if (a[i]) b[++nb] = a[i];
        }

        bool ok = true;
        int now = 0;
        FOR(i,1,m) {
            if (a[i] == 0) {
                if (full[b[now+1]]) {
                    ++now;
                    if (now <= nb) {
                        int x = b[now];
                        res[i] = x;
                        full[x] = false;
                    }
                }
            }
            else {
                if (full[a[i]]) {
                    ok = false;
                    break;
                }
                full[a[i]] = true;
            }
        }

        if (ok) {
            puts("YES");
            FOR(i,1,m) if (a[i] == 0) printf("%d ", res[i]);
            puts("");
        }
        else puts("NO");
    }
    return 0;
}