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title: 1814. Count Nice Pairs in an Array
tags: [LeetCode]

---

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###### tags: `LeetCode`
# 1814. Count Nice Pairs in an Array


## 題目
<a href = "https://leetcode.com/problems/count-nice-pairs-in-an-array/description/?envType=daily-question&envId=2023-11-21"><i class="	fa fa-bug"></i> 題目連結</a>

## 程式碼

```cpp=
class Solution {
public:
    int countNicePairs(vector<int>& nums) {
        map<int, int> m;
        int n = nums.size(), ans = 0, mod = 1000000007;
        for(int i = 0;i < n;i ++){
            int condi = nums[i] - rev(nums[i]);
            ans += m[condi];
            ans %= mod;
            m[condi] ++;
        }
        return ans;
    }

private:
    int rev(int num){
        int re = 0;
        while(num){
            re = re * 10 + num % 10;
            num /= 10;
        }
        return re;
    }
};
```
## DATE

2023/11/21