題目描述
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 (≤10^?4?? ) 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. Notice that the first digit must not be zero.
Sample Input:
5 32 321 3214 0229 87
Sample Output:
22932132143287
思路
巧妙利用cmp函數(shù)
代碼
#include <iostream>
#include <string>
#include <vector>
#include <algorithm>
using namespace std;
bool cmp1(string a, string b) {
return a + b < b + a;
}
int main() {
int n;
scanf("%d", &n);
vector<string> v(n);
for (int i = 0; i < n; i++) cin >> v[i];
sort(v.begin(), v.end(), cmp1);
string sum="";
for (int i = 0; i < n; i++) sum += v[i];
while (sum.length() != 0 && sum[0] == '0')
sum.erase(sum.begin());
if (sum.length() == 0) cout << "0";
cout << sum;
return 0;
}
