This Presentation explains decision making statements of C language

1. Made By:
Neel Pradip Shah (13CP612)
(130110107048)
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2. There are some situations where one may
have to
 Change the order of execution based on
certain conditions
OR
 Repeat a group of statements until certain
conditions are satisfied.
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3. For this, C supports some statements which are
capable of decision making, they are:
1. If statement
2. Switch statement
3. Conditional Operator
4. Goto Statement
5. While loop
6. Do-While loop
7. For loop
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4. Syntax
if(test expression)
{
statement
Block;
}
statement X;
Test
expression
?
Statement - block
Statement - X
Next Statement
TRUE
FALSE
ENTRY
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5. Syntax
if(test expression)
{
statement
Block(true);
}
else
{
statement
Block(false);
}
statement X;
Test
expression
?
Statement - block
Statement - X
TRUE
ENTRY
Statement - block
FALSE
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6. Syntax
switch(expression)
{
case value-1:
block-1;
break;
case value-2:
block-2;
break;
……………..
……………..
default
block;
break;
}
Statement - X 6

7.  It is used for an unconditional jump
Syntax
(forward jump) (backward jump)
goto label; label:
…………….. Statement;
…………….. ………………
Label: ………………
Statement; goto label;
 Programmers avoid using this
 As this statement makes logic complicated and
debugging is difficult.
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8.  An Entry Controlled loop
 Syntax
while(test condition)
{
Body Of the Loop
}
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9.  An Exit Controlled loop
 Syntax
do
{
set of statements
}
while(condition);
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10.  An Entry Controlled Loop
 Syntax
for(initialization ; test-condition ; increment)
{
BODY OF THE LOOP
}
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11. for(initialization ; test-condition ; increment)
{
BODY OF THE LOOP
}
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12. Entry
True
False
Entry
False
True
Test
Condition
Test
Condition
Body of
The loop
Body of
The loop
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13. a=10; for(a=10; a!=0; a--)a=10; for(a=10; a!=0; a--)
while(a != 0)while(a != 0) {{
{ printf(“%d”,a);{ printf(“%d”,a);
}}
printf(“%d”,a);printf(“%d”,a);
a--;a--;
}}
a=10;a=10;
dodo
{ OUTPUT : 10987654321{ OUTPUT : 10987654321
Printf(“%d”,a);Printf(“%d”,a);
a--;a--;
}}
while(a!=0)while(a!=0)
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14.  ANSI C By E.Balagurusamy
 Programming With C By Byron S Gottfried
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