1 #include<cstdio>
2
3 #include<cstdlib>
4
5 #include<cmath>
6
7 #include<cstring>
8
9 #include<algorithm>
10
11 #include<iostream>
12
13 #include<vector>
14
15 #include<map>
16
17 #include<set>
18
19 #include<queue>
20
21 #include<string>
22
23 #define inf 1000000000
24
25 #define maxn 200000+5
26
27 #define maxm 200000+5
28
29 #define eps 1e-10
30
31 #define ll long long
32
33 #define pa pair<int,int>
34
35 #define for0(i,n) for(int i=0;i<=(n);i++)
36
37 #define for1(i,n) for(int i=1;i<=(n);i++)
38
39 #define for2(i,x,y) for(int i=(x);i<=(y);i++)
40
41 #define for3(i,x,y) for(int i=(x);i>=(y);i--)
42
43 #define for4(i,x) for(int i=head[x],y=e[i].go;i;i=e[i].next,y=e[i].go)
44
45 #define for5(n,m) for(int i=1;i<=n;i++)for(int j=1;j<=m;j++)
46
47 #define mod 1000000007
48
49 #define lch k<<1,l,mid
50
51 #define rch k<<1|1,mid+1,r
52
53 using namespace std;
54
55 inline int read()
56
57 {
58
59 int x=0,f=1;char ch=getchar();
60
61 while(ch<‘0‘||ch>‘9‘){if(ch==‘-‘)f=-1;ch=getchar();}
62
63 while(ch>=‘0‘&&ch<=‘9‘){x=10*x+ch-‘0‘;ch=getchar();}
64
65 return x*f;
66
67 }
68 struct cp
69 {
70 double x,y;
71 cp operator +(cp b){return (cp){x+b.x,y+b.y};}
72 cp operator -(cp b){return (cp){x-b.x,y-b.y};}
73 cp operator *(cp b){return (cp){x*b.x-y*b.y,x*b.y+y*b.x};}
74 cp operator *(double b){return (cp){b*x,b*y};}
75 };
76 cp a[maxn],b[maxn],c[maxn],d[maxn];
77 int n=131072,m,rev[maxn];
78 const double pi=acos(-1.0);
79 void prepare()
80 {
81 int len=17;
82 for0(i,n-1)
83 {
84 int j=i,t=0;
85 for1(k,len)t<<=1,t^=j&1,j>>=1;
86 rev[i]=t;
87 }
88 }
89 inline void fft(cp x[],int n,int v)
90 {
91 for0(i,n-1)if(rev[i]>i)swap(x[i],x[rev[i]]);
92 for(int i=2;i<=n;i<<=1)
93 {
94 cp wn=(cp){cos(2.0*pi/i*v),sin(2.0*pi/i*v)};
95 for(int j=0;j<n;j+=i)
96 {
97 cp w=(cp){1,0};int mid=i>>1;
98 for0(k,mid-1)
99 {
100 cp u=x[j+k],v=x[j+k+mid]*w;
101 x[j+k]=u+v;x[j+k+mid]=u-v;
102 w=w*wn;
103 }
104 }
105 }
106 if(v==-1)for0(i,n-1)x[i].x/=n;
107 }
108
109 int main()
110
111 {
112
113 freopen("input.txt","r",stdin);
114
115 freopen("output.txt","w",stdout);
116
117 m=read();
118 for1(i,m)
119 {
120 int x=read();
121 a[x].x=b[2*x].x=c[3*x].x=1;
122 }
123 prepare();
124 fft(a,n,1);fft(b,n,1);fft(c,n,1);
125 for0(i,n-1)d[i]=a[i]+(a[i]*a[i]-b[i])*0.5+(a[i]*a[i]*a[i]-a[i]*b[i]*3.0+c[i]*2.0)*(1.0/6.0);
126 fft(d,n,-1);
127 for0(i,n-1)
128 {
129 ll x=d[i].x+0.5;
130 if(x)printf("%d% lld\n",i,x);
131 }
132
133 return 0;
134
135 }
