PAT_A1038#Recover the Smallest Number

Source:

PAT A1038 Recover the Smallest Number (30 分)

Description:

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 (≤) followed by Nnumber 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. Notice that the first digit must not be zero.

Sample Input:

5 32 321 3214 0229 87

Sample Output:

22932132143287

Keys:

• 贪心

Code:

/*
Data: 2019-07-23 18:47:04
Problem: PAT_A1038#Recover the Smallest Number
AC: 16:22

题目大意：
给几个数，求拼成的最小数
*/
#include<cstdio>
#include<string>
#include<iostream>
#include<algorithm>
using namespace std;
const int M=1e4+10;
string s[M];

bool cmp(string a, string b)
{
    return a+b < b+a;
}

int main()
{
#ifdef    ONLINE_JUDGE
#else
    freopen("Test.txt", "r", stdin);
#endif

    int n;
    scanf("%d", &n);
    for(int i=0; i<n; i++)
        cin >> s[i];
    sort(s,s+n,cmp);
    string ans="";
    for(int i=0; i<n; i++)
        ans += s[i];
    while(ans.size()>1 && ans[0]=='0')
        ans.erase(0,1);
    cout << ans;

    return 0;
}