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

Code mẫu của ladpro98

#include <iostream>
#include <algorithm>
#include <cstdio>
#include <cmath>
#include <cstring>
#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 LL long long
const int N = 1000006;
using namespace std;
char a[N], b[N];
int MOD;

bool isPrime(int x) {
    REP(i, 2, sqrt(x))
        if (x % i == 0) return 0;
   return 1; 
}

int Phi(int x) {
    int ans = x;
    int lim = sqrt(x);
    REP(i, 2, lim) 
    if (x % i == 0) {
        if (isPrime(i))
            ans = ans / i * (i - 1);
        if (i * i != x) {
            int y = x / i;
            if (isPrime(y))
                ans = ans / y * (y - 1);
        } 
    }
    return ans;
}

int bigMod(char *s, int mod) {
    LL ans = 0, n = strlen(s);
    FOR(i, 0, n) ans = (ans * 10 + s[i] - '0') % mod;
    return ans;
}

int POW(int a, int p) {
    if (p == 1) return a;
    LL x = POW(a, p >> 1);
    x = x * x % MOD;
    if (p & 1) x = x * a % MOD;
    return x;
}

int main() {
    ios :: sync_with_stdio(0); cin.tie(0);
    //freopen("tnhtest.in", "r", stdin);
    cin >> a; cin >> b; cin >> MOD;
    int phi = Phi(MOD);
    int aa = bigMod(a, MOD);
    int bb = bigMod(b, phi);
    cout << POW(aa, bb);
    return 0;
}

Code mẫu của RR

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

#define FOR(i,a,b) for(int i = a; i <= b; ++i)
#define FORD(i,a,b) for(int i = a; i >= b; --i)
#define REP(i,a) for(int i = 0; i < a; ++i)
#define MP make_pair
#define PB push_back
using namespace std;

char s[1000111], b[1000111];
int x[10111000];
int c;

long long power(long long x, int k) {
    if (!k) return 1;
    if (k == 1) return x;
    long long mid = power(x, k >> 1);
    mid = (mid * mid) % c;
    if (k & 1) return (mid * x) % c;
    else return mid;
}

int main() {
    gets(s); gets(b);
    scanf("%d", &c);
    long long a = 0;
    int l = strlen(s);
    REP(i,l) {
        a = (a * 10 + s[i] - '0') % c;
    }
    long long res = 1, p = a;
    l = strlen(b);
    FORD(i,l-1,0) {
        res = res * power(p, b[i]-'0') % c;
        p = power(p, 10);
    }
    cout << res << endl;
    return 0;
}

Code mẫu của hieult

#include <set>
#include <map>
#include <list>
#include <cmath>
#include <ctime>
#include <deque>
#include <queue>
#include <stack>
#include <bitset>
#include <cctype>
#include <cstdio>
#include <string>
#include <vector>
#include <cassert>
#include <cstdlib>
#include <cstring>
#include <sstream>
#include <iomanip>
#include <iostream>
#include <algorithm>

using namespace std;

typedef long long ll;
//typedef long double ld;
typedef double ld;
typedef unsigned int ui;
typedef unsigned long long ull;

#define Rep(i,n) for(__typeof(n) i = 0; i < (n); ++i)
#define Repd(i,n) for(__typeof(n) i = (n)-1; i >= 0; --i)
#define For(i,a,b) for(__typeof(b) i = (a); i <= (b); ++i)
#define Ford(i,a,b) for(__typeof(a) i = (a); i >= (b); --i)
#define Fit(i,v) for(__typeof((v).begin()) i = (v).begin(); i != (v).end(); ++i)
#define Fitd(i,v) for(__typeof((v).rbegin()) i = (v).rbegin(); i != (v).rend(); ++i)
#define mp make_pair
#define pb push_back
#define fi first
#define se second
#define sz(a) ((int)(a).size())
#define all(a) (a).begin(), (a).end()
#define ms(a,x) memset(a, x, sizeof(a))
#define nl puts("")
#define sp printf(" ")
#define ok puts("ok")
//#include <conio.h>

template<class F, class T> T convert(F a, int p = -1) { stringstream ss; if (p >= 0) ss << fixed << setprecision(p); ss << a; T r; ss >> r; return r; }
template<class T> void db(T a, int p = -1) { if (p >= 0) cout << fixed << setprecision(p); cout << a << " "; }
template<class T> T gcd(T a, T b) { T r; while (b != 0) { r = a % b; a = b; b = r; } return a; }
template<class T> T lcm(T a, T b) { return a / gcd(a, b) * b; }
template<class T> T sqr(T x) { return x * x; }
template<class T> T cube(T x) { return x * x * x; }
template<class T> struct Triple { T x, y, z; Triple() {} Triple(T _x, T _y, T _z) : x(_x), y(_y), z(_z) {} };
template<class T> Triple<T> euclid(T a, T b) { if (b == 0) return Triple<T>(1, 0, a); Triple<T> r = euclid(b, a % b); return Triple<T>(r.y, r.x - a / b * r.y, r.z); }
template<class T> int getbit(T s, int i) { return (s >> i) & 1; }
template<class T> T onbit(T s, int i) { return s | (T(1) << i); }
template<class T> T offbit(T s, int i) { return s & (~(T(1) << i)); }
template<class T> int cntbit(T s) { return s == 0 ? 0 : cntbit(s >> 1) + (s & 1); }
const int bfsz = 1 << 16; char bf[bfsz + 5]; int rsz = 0;int ptr = 0;
char gc() { if (rsz <= 0) { ptr = 0; rsz = fread(bf, 1, bfsz, stdin); if (rsz <= 0) return EOF; } --rsz; return bf[ptr++]; }
void ga(char &c) { c = EOF; while (!isalpha(c)) c = gc(); }
int gs(char s[]) { int l = 0; char c = gc(); while (isspace(c)) c = gc(); while (c != EOF && !isspace(c)) { s[l++] = c; c = gc(); } s[l] = '\0'; return l; }
template<class T> bool gi(T &v) {
    v = 0; char c = gc(); while (c != EOF && c != '-' && !isdigit(c)) c = gc(); if (c == EOF) return false; bool neg = c == '-'; if (neg) c = gc();
    while (isdigit(c)) { v = v * 10 + c - '0'; c = gc(); } if (neg) v = -v; return true;
}

const double PI = 2 * acos(0);
const string months[] = {"January", "February", "March", "April", "May", "June", "July", "August", "September", "October", "November", "December"};
const int days[] = {31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
const int dr[] = {0, 0, -1, +1};
const int dc[] = {-1, +1, 0, 0};
const int inf = (int)1e9 + 5;
const ll linf = (ll)1e16 + 5;
const double eps = ld(1e-9);
//const ll mod = 100000007;
typedef pair<int, int> II;


#define maxn 1000005

char sa[maxn], sb[maxn];
ll c, a;

ll mu(ll x, int k){
    if(x == 0) return 0;
    if(k == 0) return 1;
    if(k == 1) return x;
    if(k & 1) return (x * mu(x, k - 1) % c);
    ll t = mu(x, k >> 1); 
    return t * t % c;
}

int main(){
//    freopen("in.txt", "r", stdin);
//    freopen("out.txt", "w", stdout);
    gs(sa); gs(sb); gi(c);
    int lena = strlen(sa), lenb = strlen(sb);
    ll mod = 1;
    ll a = 0;
    Ford(i, lena - 1, 0){
        a = (a + mod * (sa[i] - '0')) % c;
        mod = (mod * 10) % c;
    }
    ll res = 1;
    Ford(i, lenb - 1, 0){
        res = (res * mu(a, sb[i] - '0')) % c;
        a = mu(a, 10);
    }
    cout << res ;

    return 0;
}