CF 447A(DZY Loves Hash-简单判重)
2017-06-19 10:11 tlnshuju 阅读(288) 评论(0) 编辑 收藏 举报
题目大意:有一堆数扔进Hash表。求第一次出现2个数在1个格子中的情况
模拟
#include<cstdio> #include<cstring> #include<cstdlib> #include<algorithm> #include<functional> #include<iostream> #include<cmath> #include<cctype> #include<ctime> using namespace std; #define For(i,n) for(int i=1;i<=n;i++) #define Fork(i,k,n) for(int i=k;i<=n;i++) #define Rep(i,n) for(int i=0;i<n;i++) #define ForD(i,n) for(int i=n;i;i--) #define RepD(i,n) for(int i=n;i>=0;i--) #define Forp(x) for(int p=pre[x];p;p=next[p]) #define Lson (x<<1) #define Rson ((x<<1)+1) #define MEM(a) memset(a,0,sizeof(a)); #define MEMI(a) memset(a,127,sizeof(a)); #define MEMi(a) memset(a,128,sizeof(a)); #define INF (2139062143) #define F (100000007) #define MAXN (300+10) long long mul(long long a,long long b){return (a*b)%F;} long long add(long long a,long long b){return (a+b)%F;} long long sub(long long a,long long b){return (a-b+(a-b)/F*F+F)%F;} typedef long long ll; int p,n; bool b[MAXN]; int main() { // freopen("DZY Loves Hash.in","r",stdin); // freopen(".out","w",stdout); cin>>p>>n; MEM(b) For(i,n) { int x; cin>>x; x%=p; if (b[x]) {cout<<i<<endl; return 0;} else b[x]=1; } cout<<"-1"<<endl; return 0; }