Strange Addition
Unfortunately, Vasya can only sum pairs of integers (a, b), such that for any decimal place at least one number has digit 0 in this place. For example, Vasya can sum numbers 505 and 50, but he cannot sum 1 and 4.
Vasya has a set of k distinct non-negative integers d1, d2, ..., dk.
Vasya wants to choose some integers from this set so that he could sum any two chosen numbers. What maximal number of integers can he choose in the required manner?
Input
The first input line contains integer k (1 ≤ k ≤ 100) — the number of integers.
The second line contains k distinct space-separated integers d1, d2, ..., dk (0 ≤ di ≤ 100).
Output
In the first line print a single integer n the maximum number of the chosen integers. In the second line print n distinct non-negative integers — the required integers.
If there are multiple solutions, print any of them. You can print the numbers in any order.
Examples
4 100 10 1 0
4 0 1 10 100
3 2 70 3
2 2 70 sol:我太菜了,只会分类讨论一大堆情况qaq,简直就是个智障
#includeusing namespace std;typedef int ll;inline ll read(){ ll s=0; bool f=0; char ch=' '; while(!isdigit(ch)) { f|=(ch=='-'); ch=getchar(); } while(isdigit(ch)) { s=(s<<3)+(s<<1)+(ch^48); ch=getchar(); } return (f)?(-s):(s);}#define R(x) x=read()inline void write(ll x){ if(x<0) { putchar('-'); x=-x; } if(x<10) { putchar(x+'0'); return; } write(x/10); putchar((x%10)+'0'); return;}#define W(x) write(x),putchar(' ')#define Wl(x) write(x),putchar('\n')const int N=105;int n,a[N],Id[10]={ 0};inline void put0(int n){ int i; for(i=1;i<=n;i++) W(0);}int main(){ int i,j,ans=0; R(n); for(i=1;i<=n;i++) { R(a[i]); if(a[i]==0) ans++;//000 else if(a[i]<10) Id[1]=i;//00x else if(a[i]<100) { if(a[i]%10==0) Id[2]=i;//0x0 else Id[3]=i; //0xx } else { if(a[i]%100==0) Id[4]=i;//x00 else if(a[i]%10==0) Id[5]=i; //xx0; else if((a[i]-a[i]%10)%100==0) Id[6]=i; //x0x else Id[7]=i; //xxx } } if(Id[1]) { if(Id[2]) { if(Id[4]) { Wl(ans+3); put0(ans); W(a[Id[1]]); W(a[Id[2]]); W(a[Id[4]]); } else { Wl(ans+2); put0(ans); W(a[Id[1]]); W(a[Id[2]]); } } else { if(Id[4]) { Wl(ans+2); put0(ans); W(a[Id[1]]); W(a[Id[4]]); } else if(Id[5]) { Wl(ans+2); put0(ans); W(a[Id[1]]); W(a[Id[5]]); } else { Wl(ans+1); put0(ans); W(a[Id[1]]); } } } else if(Id[2]) { if(Id[4]) { Wl(ans+2); put0(ans); W(a[Id[2]]); W(a[Id[4]]); } else if(Id[6]) { Wl(ans+2); put0(ans); W(a[Id[2]]); W(a[Id[6]]); } else { Wl(ans+1); put0(ans); W(a[Id[2]]); } } else if(Id[4]) { if(Id[3]) { Wl(ans+2); put0(ans); W(a[Id[4]]); W(a[Id[3]]); } else { Wl(ans+1); put0(ans); W(a[Id[4]]); } } else if(Id[3]) { Wl(ans+1); put0(ans); W(a[Id[3]]); } else if(Id[5]) { Wl(ans+1); put0(ans); W(a[Id[5]]); } else if(Id[6]) { Wl(ans+1); put0(ans); W(a[Id[6]]); } else if(Id[7]) { Wl(ans+1); put0(ans); W(a[Id[7]]); } else { Wl(ans); put0(ans); } return 0;}/*Input4100 10 1 0Output40 1 10 100 Input32 70 3Output22 70 */