标签:long i++ problem void tmp str stream amp getchar
http://uoj.ac/problem/121 (题目链接)
给出${n}$个${d}$维向量,问是否有两个不同的向量的内积是${k}$的倍数。
又卡了一上午常数,我弃了T_T。
右转题解→_→:llg
// uoj121 #include<algorithm> #include<iostream> #include<cstdlib> #include<cstring> #include<cstdio> #include<cmath> #include<ctime> #define RG register #define LL long long #define inf (1ll<<30) #define MOD 1000000007 #define Pi acos(-1.0) #define free(a) freopen(a".in","r",stdin),freopen(a".out","w",stdout); using namespace std; inline int gi() { int x=0,f=1;char ch=getchar(); while (ch<‘0‘ || ch>‘9‘) {if (ch==‘-‘) f=-1;ch=getchar();} while (ch>=‘0‘ && ch<=‘9‘) {x=x*10+ch-‘0‘;ch=getchar();} return x*f; } const int maxn=100010,maxd=110; int a[maxn][maxd],l[maxn],r[maxn]; int u[maxn],v[maxn],p[maxn],tmp[maxn]; int n,d,K,tt; inline void inc(int &x,RG int y) { x+=y;while (x>=K) x-=K; } inline int Z(RG int i,RG int j) { if (K==2) return a[i][j]; RG int w=a[i][l[j]]*a[i][r[j]]; return w>=K ? w-K : w; } inline bool solve() { for (RG int i=1;i<=n;++i) v[i]=rand()%K,u[i]=v[i],tmp[i]=0; int sum=0,c=0; for (RG int i=1;i<=n;i++) inc(sum,v[i]); for (RG int i=1;i<=n;i++) { int t=sum-1*v[i]+p[i]*v[i]+K; v[i]=0,inc(v[i],t); } for (RG int i=1;i<=d;i++) for (RG int j=1;j<=n;j++) inc(tmp[i],u[j]*Z(j,i)); if ((double)clock()/CLOCKS_PER_SEC>=4.5) return 0; for (RG int i=1;i<=d;i++) u[i]=tmp[i],tmp[i]=0; for (RG int i=1;i<=n;i++) { for (RG int j=1;j<=d;j++) inc(tmp[i],u[j]*Z(i,j)); if (tmp[i]!=v[i]) {c=i;break;} } if (!c) return 0; for (RG int i=1;i<=n;i++) if (i!=c) { RG int q=0; for (RG int j=1;j<=tt;j++) inc(q,a[i][j]*a[c][j]); if (!q) { printf("%d %d\n",min(i,c),max(i,c)); return 1; } } return 1; } int main() { srand(time(NULL)); n=gi(),d=gi(),K=gi(); for (RG int i=1;i<=n;i++) for (RG int j=1;j<=d;j++) a[i][j]=gi()%K; tt=d; if (K==3) { d*=d; for (RG int i=1;i<=d;i++) l[i]=(i-1)%tt+1,r[i]=(i-l[i])/tt+1; } for (RG int i=1;i<=n;i++) { for (RG int j=1;j<=tt;j++) inc(p[i],a[i][j]); if (K==3) (p[i]*=p[i])%=K; } RG int T=5,flag=0; while (T--) { flag=solve(); if (flag) break; } if (!flag) puts("-1 -1"); //printf("%.3lf",(double)clock()/CLOCKS_PER_SEC); return 0; }
标签:long i++ problem void tmp str stream amp getchar
原文地址:http://www.cnblogs.com/MashiroSky/p/6388772.html