413. Arithmetic Slices

Description

Solution

Iteration to find start & end of each Arithmetic

Code

class Solution {
public:
    int numberOfArithmeticSlices(vector<int>& nums) {
        if(nums.size() < 3)
            return 0;
        vector<int> diff(nums.size()-1);
        for(int i = 1; i < nums.size(); i++){
            diff[i-1] = nums[i] - nums[i-1];
        }
        int prev = diff[0], count = 0, res = 0;
        for(int i = 1; i < diff.size(); i++){
            if(prev == diff[i]){
                count++;
                res += count;
            }else{
                count = 0;
            }
            prev = diff[i];
        }
        return res;
    }
};