#Nested while loop
#row=1
#while row<=5:#outerloop
#    col=1
#    while col<=5:#inner loop
#        print(col,end=' ')
#        col+=1
#    print()#to line break 
#    row+=1

#row=1
#while row<=3:#outerloop
#    col=1
#    while col<=4:#inner loop
#        print(col+row,end=' ')
#        col+=1
#    print()#to line break 
#    row+=1
    
#col<=row
#row=1
#while row<=4:#outerloop
#    col=1
#    while col<=row:#inner loop
#        print(col,end=' ')
#        col+=1
#    print()#to line break 
#    row+=1
    
#row+col
#row=1
#while row<=4:#outerloop
#    col=1
#    while col<=4:#inner loop
#        print(row+col,end=' ')
#        col+=1
#    print()#to line break 
#    row+=1
    
#col-row
#row=1
#while row<=4:#outerloop
#    col=1
#    while col<=4:#inner loop
#        print(col-row,end=' ')
#        col+=1
#    print()#to line break 
#    row+=1    

#col*row
row=1
while row<=4:#outerloop
    col=1
    while col<=4:#inner loop
        print(col*row,end=' ')
        col+=1
    print()#to line break 
    row+=1  
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    