Syntax :
      while <condition>;
                statements block 1
       [else:
                statements block2]

Code :
n1 = int(input(:Enter the first number:"))
n2 = int(input("Enter the second number:")
n3 = int(input(:Enter the third number:")
if(n1?=n2) and(n1>=n3) :
        biggest = n1 ;
elif(n2>=nl)and (n2>=n3) :
        biggest = n2
else:
        biggest = n3
print("The biggest number between",n1,",",n2"and"n3"is",biggest)
Output :
Enter the first number : 1
Enter the second number : 3 
Enter the third number : 5
The biggest number between 1, 3 and 5 is 5

(i) The if.. else statement provides control to check the true block as well as the false block,
(ii) Syntax :
     if <condition> :
           statemets-block 1
     else :
           statement-block 2
(iii) if..else statement thus provides possibilities and the condition  determines which BLOCK is to be executed.

for i in range (1, 6) :
for j in range (65, 65 + i)
         a = chr(j)
print a
print

(i) for i in range (5, 0,-1):
for j in range (1, i + 1):
print (i, end =' ')
print (end = '\n')
i+ = 1
(ii) for i in range (5, 0, -1):
for j in range (1, i + 1):
print (j end =' ')
print (i, end = '\n')
i+ = 1

for i in range (1,6):
for j in range (1, i+1)
print (i, end =' ')
print (end = '\n')
i+ = 1

i=1
while (i < = 6):
for j in range (1,i):
print (j,end='\t')
print (end='\n')
i+=1
Output:
1
1 2
1 2 3
1 2 3 4
1 2 3 4 5

The jump statement in Python, is used to unconditionally transfer the control from one part of the program to another. There are three keywords to achieve jump statements in Python: break, continue, pass. The following flowchart illustrates the use of break and continue.

(i) break statement: The break statement terminates the loop containing it. Control of the program flows to the statement immediately after the body of the loop. A while or for loop will iterate till the condition is tested false, but one can even transfer the control out of the loop (terminate) with help of break statement. When the break statement is executed, the control flow of the program comes out of the loop and starts executing the segment of code after the loop structure. If break statement is inside a nested loop (loop inside another loop), break will terminate the innermost loop.
Syntax:
break
(ii) Continue statement: Continue statement unlike the break statement is used to skip the remaining part of a loop and start with next iteration.
Syntax:
continue
(iii) Pass statement: pass statement is generally used as a placeholder. When we have a loop or function that is to be implemented in the future and not now, we cannot develop such functions or loops with empty body segment because the interpreter would raise an error. So, to avoid this we can use pass statement to construct a body that does nothing.
Syntax:
pass

Nested if..elif..else statement :
(i) When we need to construct a chain of if statement(s) then 'elif' clause can be used instead of 'if else'.
(ii) Syntax:
if < condition - 1>:
      statements-block 1
elif < condition - 2>:
       statements-block 2
else:
       statements-block n
(iii) In the syntax of if..elif ..else mentioned above, condition -1 is tested if it is true then statements-block 1 is executed, otherwise, the control checks condition-2, if it is true statements-block 2 is executed and even if it fails statements-block n mentioned in else part is executed.

(iv) 'elif' clause combines if..else-if ..else statements to one if..elif ... else. 'elif' can be considered to be abbreviation of 'else if'. In an 'if' statement there is no limit of 'elif' clause that can be used, but an 'else' clause if used should be placed at the end.
(v) Example: # Program to illustrate the use of nested if statement

m1 = int (input("Enter mark in first subject:"))
m2 = int (input("Enter mark in second subject:"))
avg = (m1+m2)/2
if avg > =80:
   print ("Grade : A")
elif avg > =70 and avg < 80:
   print ("Grade : B")
elif avg > =60 and avg < 70:
   print ("Grade : C")
elif avg > =50 and avg < 60:
   print ("Gradec: D")
else:
   print("Grade : E")
Output 1:
Enter mark in first subject : 34
Enter mark in second subject : 78
Grade : D
Output 2:
Enter mark in first Subject : 67
Enter mark in  second subject : 73
Grade: B