题解 | #缺失的第一个正整数#

#include <unordered_map>
class Solution {
public:
    /**
     * 代码中的类名、方法名、参数名已经指定，请勿修改，直接返回方法规定的值即可
     *
     * 
     * @param nums int整型vector 
     * @return int整型
     */
    int minNumberDisappeared(vector<int>& nums) {
        // write code here
        unordered_map<int, int> num_and_occur;
        for (auto& item : nums) {
            num_and_occur[item]++;
        }
        int i = 1;
        while (num_and_occur.count(i) > 0) {
            i++;
        }
        return i;
    }
};