import pickle
def add():
    f=open('student.dat','ab')
    while True:
        rollno=int(input('enter rollno'))
        name=input('enter name')
        per=int(input('enter percentage'))
        pickle.dump([rollno,name,per],f)
        ch=input('want to add more? y/n')
        if ch=='n':
            break
    f.close()
def show():
    f=open('student.dat','rb')
    try:
        while True:
            print(pickle.load(f))
    except:
        pass
    f.close()

def search(p):
    f=open('student.dat','rb')
    try:
        while True:
            d=pickle.load(f)
            if d[2]>75:
                print(d)
    except:
        pass
    f.close()

while True:
    print('1.ADD student ')
    print('2.Show all students')
    print('3.Search student')
    print('4 Exit')
    ch=int(input('enter choice'))
    if ch==1:
        add()
    elif ch==2:
        show()
    elif ch==3:
        n=int(input('enter percentage for search student'))
        search(n)
    elif ch==4:
        break
'''
OUTPUT
1.ADD student 
2.Show all students
3.Search student
4 Exit
enter choice1
enter rollno1
enter nameaditya
enter percentage87
want to add more? y/ny
enter rollno2
enter namereema
enter percentage68
want to add more? y/ny
enter rollno3
enter namesuniya
enter percentage70
want to add more? y/nn
1.ADD student 
2.Show all students
3.Search student
4 Exit
1.ADD student 
2.Show all students
3.Search student
4 Exit
enter choice2
[1, 'aditya', 87]
[2, 'reema', 68]
[3, 'suniya', 70]

1.ADD student 
2.Show all students
3.Search student
4 Exit
enter choice3
enter percentage for search student76
[1, 'aditya', 87]
1.ADD student 
2.Show all students
3.Search student
4 Exit
enter choice4
'''