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#include <iostream>
#include <cstdio>
#include <algorithm>
#include <cstring>
#include <cmath>
#include <queue>
#include <set>
#include <vector>
using namespace std;
const int INF = ~0u>>1;
typedef pair <int,int> P;
typedef long long llg;
#define MID(x,y) ((x+y)>>1)
#define iabs(x) ((x)>0?(x):-(x))
#define REP(i,a,b) for(int i=(a);i<(b);i++)
#define FOR(i,a,b) for(int i=(a);i<=(b);i++)
#define pb push_back
#define mp make_pair
#define print() cout<<"--------"<<endl
const int N = 100003;
struct Baby_step_Giant_step{
struct edge{int key,times;edge*next;}g[N],*ls[N];
int e;
void add(int x,int times){
int hash = x % N;
for (edge*t=ls[hash];t;t=t->next)
if(t->key == x) return ;
g[++e].key = x;
g[e].times = times;
g[e].next = ls[hash];
ls[hash] = &g[e];
}
int In(int x){
int hash = x % N;
for (edge*t=ls[hash];t;t=t->next)
if(t->key == x) return t->times;
return -1;
}
int Power_mod(int a,int b,int mod){
llg t = a, res = 1;
while (b){
if (b&1) res = res * t % mod;
t = t * t % mod;
b >>= 1;
}
return (int)(res);
}
llg exgcd(int a,int b,llg &x,llg &y){
if (b == 0){
x = 1; y = 0; return a;
}
llg g = exgcd(b,a%b,x,y);
llg tx = x,ty = y;
x = ty; y = tx - a/b*ty;
return g;
}
int solve(int a,int c,int p){
if (c >= p) return -1;
int i,j;
int x = 1; int t = 1;
int s = (int)ceil(sqrt((double)p));
int res,cnt = 0;
llg tx,ty,g;
for (int i = 0; i <= 50; i++)
if (Power_mod(a,i,p) == c)
return i;
while ((g=exgcd(a,p,tx,ty)) != 1){
if (c%g) return -1;
c /= g;
p /= g;
x = (llg)(a)/g*x%p;
cnt ++;
}
e = 0;
memset(ls,0,sizeof(ls));
for (i = 0; i < s; i++) add(Power_mod(a,i,p),i);
for (int step = Power_mod(a,s,p),i = cnt; i < p;
i += s,x = (llg)(x) * step % p){
g = exgcd(x,p,tx,ty);
tx = tx * c % p;
if (tx < 0) tx += p;
res = In((int)tx);
if (res == -1) continue;
return res + i;
}
return -1;
}
}Number_Theory;
int main(){
int a,p,c;
while(~scanf("%d%d%d", &a, &p, &c)){
int ans = Number_Theory.solve(a,c,p);
if (ans == -1) puts("Orz,I can’t find D!");
else printf("%dn", ans);
}
return 0;
}
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