Binary Subarrays With Sum LeetCode solution in C++

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class Solution {
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 public:
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  int lessequal(vector<int> &nums, int goal) {
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    if (goal < 0) return 0;
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    int n = nums.size();
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    int i = 0, j = 0;
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    int sum = 0;
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    int ans = 0;
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    while (j < n) {
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      sum += nums[j];
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      while (sum > goal) {
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        sum -= nums[i];
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        i++;
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      }
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      ans += j - i + 1;
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      j++;
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    }
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    return ans;
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  }
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  int numSubarraysWithSum(vector<int> &nums, int goal) {
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    return lessequal(nums, goal) - lessequal(nums, goal - 1);
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  }
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};
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// our function is giving number of subarrays with sum less or equal to goal.
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// upvote if it helps.