#include <iostream>
#include <vector>
#include <algorithm>
 
using namespace std;
 
int main() {
    int T;
    cin >> T;
 
    while (T--) {
        int n;
        cin >> n;
 
        vector<int> heights(n);
        for (int i = 0; i < n; ++i) {
            cin >> heights[i];
        }
 
        int maxLength = 0;
 
        // Try adjusting each possible subarray
        for (int i = 0; i < n; ++i) {
            for (int j = i; j < n; ++j) {
                int minHeight = *min_element(heights.begin() + i, heights.begin() + j + 1);
                int maxHeight = *max_element(heights.begin() + i, heights.begin() + j + 1);
 
                // Check if it's possible to adjust the subarray by modifying it
                if (maxHeight - minHeight <= j - i) {
                    maxLength = max(maxLength, j - i + 1);
                }
            }
        }
 
        cout << maxLength << endl;
    }
 
    return 0;
}
 

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10
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