LeetCode Daily Problem P2221 Triangular Sum of an Array

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Timeline

Timeline

2025-10-01

init

Math, Simulation

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Problem:

P2221 Triangular Sum of an Array

https://leetcode.cn/problems/find-triangular-sum-of-an-array/description/?envType=daily-question&envId=2025-10-01

Math Simulation

#include <vector>
using std::vector;

class Solution {
public:
  int triangularSum(vector<int> &nums) {
    int i;
    int bound;
    int n = nums.size();

    for (int k = 0; k < n; k++) {
      i = 0;
      bound = n - k;
      while (i < bound - 1) {
        nums[i] = (nums[i] + nums[i + 1]) % 10;
        i++;
      }
    }
    return nums[0];
  }
};