$Noip2014/Luogu2312$ 解方程
$Sol$
枚举解+秦九韶公式计算+取模.
$Code$
#include<iostream> #include<cstdio> #include<cstring> #include<queue> #include<algorithm> #define il inline #define Rg register #define go(i,a,b) for(Rg int i=a;i<=b;++i) #define yes(i,a,b) for(Rg int i=a;i>=b;--i) #define e(i,u) for(Rg int i=b[u];i;i=a[i].nt) #define mem(a,b) memset(a,b,sizeof(a)) #define ll long long #define ull unsigned long long #define db double #define inf 2147483647 using namespace std; const int N=1000010,mod=1000000007; il int read() { ll x=0;int y=1;char c=getchar(); while(c<'0'||c>'9'){if(c=='-')y=-1;c=getchar();} while(c>='0'&&c<='9'){x=((x<<1)%mod+(x<<3)%mod+c-'0')%mod;c=getchar();} return x*y; } int n,m,ct,as[N],a[N]; il bool ck(int x) { ll ret=0; yes(i,n,0)ret=(ret*x%mod+a[i])%mod; if(ret==0)return 1;return 0; } int main() { n=read(),m=read(); go(i,0,n)a[i]=read(); go(i,1,m)if(ck(i))as[++ct]=i; printf("%d\n",ct); go(i,1,ct)printf("%d\n",as[i]); return 0; }
光伴随的阴影