codeforces C. Division 数学
http://codeforces.com/contest/1445/problem/C
1 #include<cstdio> 2 #define rep(i,a,n) for(register ll i = a;i <= n;++i) 3 #define per(i,n,a) for(register ll i = n;i >= a;--i) 4 using namespace std; 5 typedef long long ll; 6 7 const ll Maxn = 100011; 8 9 ll read(){ 10 ll a = 0;char c = getchar(),l = c; 11 while(c < '0'||c > '9')l = c,c = getchar(); 12 while('0' <= c&&c <= '9')a = a*10+c-'0',c = getchar(); 13 if(l == '-')return -a;return a; 14 } 15 16 ll max(ll a,ll b){if(a > b)return a;return b;} 17 18 ll prime[Maxn],v[Maxn],b[Maxn]; 19 ll cntp; 20 21 void euler(){ 22 cntp = 0; 23 rep(i,2,100010){ 24 if(!v[i])v[i] = i,prime[++cntp] = i; 25 rep(j,1,cntp){ 26 if(prime[j] > v[i]||prime[j]*i > 100010)break; 27 v[prime[j]*i] = prime[j]; 28 } 29 } 30 31 } 32 33 int main(){ 34 euler(); 35 ll t = read(); 36 while(t--){ 37 ll x = read(),y = read(),ans = 1,z = y,cnt = 0; 38 rep(i,1,cntp)if(z%prime[i] == 0){ 39 b[++cnt] = prime[i];//printf("working %d:\n",b[cnt]); 40 while(z%prime[i] == 0)z /= prime[i]; 41 } 42 if(z > 1)b[++cnt] = z; 43 rep(i,1,cnt){ 44 ll cntx = 0,cnty = 0,xx = x,yy = y; 45 while(yy % b[i] == 0)yy /= b[i],cnty++; 46 while(xx % b[i] == 0)xx /= b[i],cntx++; 47 if(cntx < cnty){ans = x;break;} 48 else{ 49 rep(j,1,cnty-1)xx *= b[i]; 50 // printf("---- %%%d %d\n",b[i],xx); 51 ans = max(ans,xx); 52 } 53 } 54 if(ans == 1){ 55 while(x % y == 0)x /= y; 56 ans = x; 57 } 58 printf("%lld\n",ans); 59 } 60 return 0; 61 }
