text: def minPlatform(n, arr, dep):
  	arr.sort() 
      dep.sort() 
      plat_needed = 1
      result = 1
      i = 1
      j = 0
      while (i < n and j < n): 
          if (arr[i] <= dep[j]):
              plat_needed+= 1
              i+= 1
          elif (arr[i] > dep[j]):
              plat_needed-= 1
              j+= 1
          if (plat_needed > result):  
              result = plat_needed 
            
      return result
  
  if __name__ == "__main__":
  	arr = [0900,  0940, 0950, 1100, 1500, 1800]
  	dep = [0910, 1200, 1120, 1130, 1900, 2000]
  	print(minPlatform(len(arr), arr, dep))