CodeForce 614B Gena's Code 巧用字符串

B. Gena's Code

time limit per test

0.5 seconds

memory limit per test

256 megabytes

input

standard input

output

standard output

It's the year 4527 and the tanks game that we all know and love still exists. There also exists Great Gena's code, written in 2016. The problem this code solves is: given the number of tanks that go into the battle from each country, find their product. If it is turns to be too large, then the servers might have not enough time to assign tanks into teams and the whole game will collapse!

There are exactly n distinct countries in the world and the i-th country added ai tanks to the game. As the developers of the game are perfectionists, the number of tanks from each country is beautiful. A beautiful number, according to the developers, is such number that its decimal representation consists only of digits '1' and '0', moreover it contains at most one digit '1'. However, due to complaints from players, some number of tanks of one country was removed from the game, hence the number of tanks of this country may not remain beautiful.

Your task is to write the program that solves exactly the same problem in order to verify Gena's code correctness. Just in case.

Input

The first line of the input contains the number of countries n (1 ≤ n ≤ 100 000). The second line contains n non-negative integers aiwithout leading zeroes — the number of tanks of the i-th country.

It is guaranteed that the second line contains at least n - 1 beautiful numbers and the total length of all these number's representations doesn't exceed 100 000.

Output

Print a single number without leading zeroes — the product of the number of tanks presented by each country.

Sample test(s)

input

3
5 10 1

output

50

input

4
1 1 10 11

output

110

input

5
0 3 1 100 1

output

0

Note

In sample 1 numbers 10 and 1 are beautiful, number 5 is not not.

In sample 2 number 11 is not beautiful (contains two '1's), all others are beautiful.

In sample 3 number 3 is not beautiful, all others are beautiful.

題意：求給出的數的乘積，每組數據最多有一個不美麗的數。

題解：由於數據範圍過大， 直接相乘不可取，這裏只能用字符串模擬。有不美麗的數就把不美麗的數放在字符串最前面，沒有的話就放1在最前面，然後計數所有數據中0的個數，最後一起輸出即爲最後的結果。

#include<cstdio>
#include<cstring>
#include<iostream>
#include<algorithm>
#include<cmath>
#include<queue>
#include<cstdlib>
#include<string>

#define inf 9999999.9
#define maxn 100010
using namespace std;

char s[maxn],ans[maxn];
int main()
{
    int n;
    while(~scanf("%d",&n))
{
    int fg=0,f=0,len=0;
       for(int i=0;i<n;i++)
       {
          scanf("%s",s);
          if(s[0]=='0')
          {
             fg=1;
             continue;
          }
            if(f==1)
            {
                len+=strlen(s)-1;
                continue;
            }
            if(s[0]!='1')
            {
                f=1;
                strcpy(ans,s);
                continue;
            }
            if(s[0]=='1')
            {
                if(strlen(s)>1)
                {
                    for(int i=1;i<strlen(s);i++)
                    {
                        if(s[i]!='0')
                        {
                            f=1;
                            strcpy(ans,s);
                            break;
                        }
                    }
                    if(f==0)
                        len+=strlen(s)-1;
                }
            }
            //printf("%d*%s   %c",f,ans,s[i]);
       }
       if(fg==1)
       {
          printf("0\n");
          break;
       }
            if(strlen(ans)!=0)
                printf("%s",ans);
            else
                printf("1");
            for(int i=0;i<len;i++)
                printf("0");
            printf("\n");
    }
  return 0;
}