#calculate velocity
                #2022/11/7
                #kumar amrit
                # coding: utf-8
                import os
                
                y = '1'
                while y == '1':
                    os.system('clear')
                
                    print('''
                      v velocity
                      d distance
                      t time
                      
                      ''')
                  
                    opr=input("Enter the opr..(v,d,t)")
                    
                
                    
                    if opr=="v":
                        num1=int(input("Enter the distance in kilometer:-"))
                        num2=int(input("Enter the time in hour :-"))  
                        print(num1/num2,"km/hrs")
                       
                    elif opr=="d":   
                        num2=int(input("Enter the time in hour :-"))
                        num3=int(input("Enter the velocity in km/hrs :-"))
                        print(num2*num3,"km")
                        
                    elif opr=="t":
                        num1=int(input("Enter the distance in kilometer:-"))
                        num3=int(input("Enter the velocity in km/hrs :-"))
                        print(num1/num3,"hour")
                        
                   
                    else:
                        print("invalid opr....")
                   
                    y = input('\n\t 計算を  1: 続ける　other:やめる\n')
                print('thanks')
                
            

実行結果