PAT A1038

1038. Recover the Smallest Number (30)

Given a collection of number segments, you are supposed to recover the smallest number from them. For example, given {32, 321, 3214, 0229, 87}, we can recover many numbers such like 32-321-3214-0229-87 or 0229-32-87-321-3214 with respect to different orders of combinations of these segments, and the smallest number is 0229-321-3214-32-87.

Input Specification:

Each input file contains one test case. Each case gives a positive integer N (<=10000) followed by N number segments. Each segment contains a non-negative integer of no more than 8 digits. All the numbers in a line are separated by a space.

Output Specification:

For each test case, print the smallest number in one line. Do not output leading zeros.

Sample Input:

5 32 321 3214 0229 87

Sample Output:

22932132143287

代码实现如下：

#include <iostream>#include <cstdio>#include <cstring>#include <algorithm>using namespace std;const int MAXN = 10010;string str[MAXN];bool cmp(string a, string b){    return a + b < b + a;}int main(){    int n;    cin>>n;    for(int i = 0; i < n; i++){        cin>>str[i];    }    sort(str, str + n, cmp);    string ans;    for(int i = 0; i < n; i++){        ans += str[i];    }    while(ans.size() != 0 && ans[0] =='0'){        ans.erase(ans.begin());    }    if(ans.size() == 0)cout<<'0';    else cout<<ans;    return 0;}