标签:force 统计 ++ piped space ack namespace The div
大意: 给定A,B,C, 求有多少个三元组$(a,b,c)$, 满足$a \le b \le c$, 且以若干个$(a,b,c)$为三边的长方体能填满边长(A,B,C)的长方体.
暴力枚举出$A,B,C$的所有整除关系的数量, 这样可以避免重复计数, 最后再用可重组合统计一下结果
#include <iostream> #include <algorithm> #include <math.h> #include <cstdio> #include <set> #include <map> #include <string> #include <vector> #include <string.h> #include <queue> #define PER(i,a,n) for(int i=n;i>=a;--i) #define REP(i,a,n) for(int i=a;i<=n;++i) #define hr cout<<‘\n‘ #define pb push_back #define mid ((l+r)>>1) #define lc (o<<1) #define rc (lc|1) #define ls lc,l,mid #define rs rc,mid+1,r #define x first #define y second #define io std::ios::sync_with_stdio(false); #define endl ‘\n‘ using namespace std; typedef unsigned long long ll; typedef pair<int,int> pii; const int P = 1e9+7; ll gcd(ll a,ll b) {return b?gcd(b,a%b):a;} ll qpow(ll a,ll n) {ll r=1%P;for (a%=P;n;a=a*a%P,n>>=1)if(n&1)r=r*a%P;return r;} void exgcd(ll a,ll b,ll &d,ll &x,ll &y){b?exgcd(b,a%b,d,y,x),y-=a/b*x:x=1,y=0,d=a;} ll inv(ll x){return x<=1?1:inv(P%x)*(P-P/x)%P;} //head const int N = 1e5+10, S = 7; int c[10], f[N]; ll C(int n, int m) { ll r = 1; REP(i,1,m) r*=n,--n; REP(i,1,m) r/=i; return r; } int check(int a,int b,int c) { if((a&1)&&(b&2)&&(c&4)) return true; if((a&1)&&(c&2)&&(b&4)) return true; if((b&1)&&(a&2)&&(c&4)) return true; if((b&1)&&(c&2)&&(a&4)) return true; if((c&1)&&(a&2)&&(b&4)) return true; if((c&1)&&(b&2)&&(a&4)) return true; return false; } void work() { int x, y, z; scanf("%d%d%d", &x, &y, &z); int xy=gcd(x,y),yz=gcd(y,z),xz=gcd(z,x),xyz=gcd(z,xy); c[7]=f[xyz]; c[6]=f[xy]-c[7]; c[5]=f[xz]-c[7]; c[3]=f[yz]-c[7]; c[4]=f[x]-c[5]-c[6]-c[7]; c[2]=f[y]-c[6]-c[3]-c[7]; c[1]=f[z]-c[5]-c[3]-c[7]; ll ans = 0; REP(i,0,7)REP(j,i,7)REP(k,j,7) if (check(i,j,k)) { int u[10]={}; ++u[i],++u[j],++u[k]; ll t = 1; REP(i,1,7) if (u[i]) t*=C(c[i]+u[i]-1,u[i]); ans += t; } printf("%llu\n", ans); } int main() { REP(i,1,N-1) for (int j=i; j<N; j+=i) ++f[j]; int t; scanf("%d", &t); while (t--) work(); }
Pave the Parallelepiped CodeForces - 1007B (计数)
标签:force 统计 ++ piped space ack namespace The div
原文地址:https://www.cnblogs.com/uid001/p/10480583.html