A community solar farm logs its daily energy output, in kilowatt-hours, for n consecutive days. Under its grid interconnection contract, auditors evaluate the farm's performance over every window of exactly k consecutive days: for each such window (there are n - k + 1 of them, sliding one day at a time), they sum that window's daily outputs. If a window's total output falls strictly below the contracted floor minOutput, the farm incurs a shortfall penalty of -1 point for that window. If the total strictly exceeds the surplus ceiling maxOutput, the farm earns a surplus bonus of +1 point. If the total lies anywhere between minOutput and maxOutput, inclusive, the window is neutral and contributes 0 points.

Compute the farm's total audit score, summed across every window.

Input format

• Line 1: two integers n and k — the number of logged days and the audit window length.
• Line 2: two integers minOutput and maxOutput (minOutput <= maxOutput) — the contracted floor and surplus ceiling.
• Line 3: n space-separated integers — the daily energy output for days 0 through n-1.

Output format

Print a single integer: the total audit score summed over all n - k + 1 windows. The score may be negative, zero, or positive.

Constraints

• 1 <= k <= n <= 100000
• 0 <= minOutput <= maxOutput <= 10^9
• 0 <= daily output <= 10000, for each of the n days

7 3
6 8
3 2 1 4 1 3 5

1

5 1
2 4
1 2 3 4 5

0