1144 The Missing Number

寻找缺失的最小正整数

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1144 The Missing Number
Given N integers, you are supposed to find the smallest positive integer that is NOT in the given list.

Input Specification:
Each input file contains one test case. For each case, the first line gives a positive integer N (≤10
5
). Then N integers are given in the next line, separated by spaces. All the numbers are in the range of int.

Output Specification:
Print in a line the smallest positive integer that is missing from the input list.

Sample Input:
10
5 -25 9 6 1 3 4 2 5 17
Sample Output:
7
题目大意：寻找一段序列中，没出现的最小正整数。
分析：将大于0的数放在v中，进行排序。如果序列中不存在负数，最小的起始数为1，相反则为v[0],
参考代码：

#include<iostream>
#include<vector>
#include<algorithm>
using namespace std;
int main() {
	vector<int>v;
	int n, temp, minn, flag = 0;
	scanf_s("%d", &n);
	for (int i = 0; i < n; i++) {
		scanf_s("%d", &temp);
		if (temp > 0) v.push_back(temp);
		else flag = 1;
	}
	sort(v.begin(), v.end());
	if (flag)minn = 1;
	else minn = v[0];
	for (int i = 0; i < v.size(); i++) {
		int j = i + 1, cnt = 1;
		while (j < v.size() && v[j] == v[i]) {
			cnt++; j++;
		}
		i += (cnt - 1);
		if (v[i] == minn) { minn++; }
		else { cout << minn; return 0; }
	}
	cout << minn;
	return 0;
}