การใช้ Turbo C ชุดที่ 6 condition โดย อ.กำธร เรือนฝายกาศ มหาวิทยาลัยเทคดนโลยีราชมงคลล้านนา วิทยาเขคภาคพายัพ

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if (condition)
{
statement_1;
statement_2;
...
statement_n;
}

3. -3-
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float dx,dy;
void main()
{
clrscr();
printf(Enter delta Y : );
scanf(%f,dy);
printf(Enter delta X : );
scanf(%f,dx);
if(dy!=0) printf(Slope = %fn,dy/dx);
getch();
}
Enter delta Y : 3
Enter delta X : 4
Slope = 0.750000
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4. -4-
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statement_A;
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statement_B;
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{
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statement_A2;
...
statement_An;
}
else
{
statement_B1;
statement_B2;
statement_Bn;
}
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5. -5-
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#include stdio.h
#include conio.h
int choice;
float radius, circum, area;
void main()
{
clrscr();
textcolor(LIGHTRED);
cprintf(Menu);
printf(n);
textcolor(LIGHTGREEN);
cprintf(1.Circumference of the circle);
printf(n);
cprintf(2.Area of the circle);
printf(n);
printf(Enter your choice 1 or 2 : );
scanf(%d,choice);
printf(Enter radius of the circle : );
scanf(%f,radius);
if(choice==1)
{
circum = 2*3.14156*radius;
printf(Circumference of the circle =
%fn,circum);
}
else
{
area = 3.14156*radius*radius;
printf(Area of the circle = %fn,area);
}
getch();
}

6. -6-
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Menu
1.Circumference of the circle
2.Area of the circle
Enter your choice 1 or 2 : 1
Enter radius of the circle : 3
Circumference of the circle = 18.84936
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Menu
1.Circumference of the circle
2.Area of the circle
Enter your choice 1 or 2 : 2
Enter radius of the circle : 3
Area of the circle = 28.274040

7. -7-
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statement_A
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}
else if(condition_C)
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statement_A
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else if(condition_n)
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8. -8-
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#include stdio.h
#include conio.h
int point;
void main()
{
clrscr();
printf(Enter your's point :);
scanf(%d,point);
if( ( point = 100 ) ( point = 80 ) )
printf(Grade = An);
else if( ( point 80 ) ( point = 70 ) )
printf(Grade = Bn);
else if( ( point 70 ) ( point = 60 ) )
printf(Grade = Cn);
else if( ( point 60 ) ( point = 50 ) )
printf(Grade = Dn);
else if( ( point 50 ) ( point = 0 ) )
printf(Grade = Fn);
getch();
}
Enter your's point :99
Grade = A

9. -9-
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case constant_A :
statement_A;
break;
case constant_B :
statement_B;
break;
...
case default :
statement;
break;
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10. -10-
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#include stdio.h
char grade;
void main()
{
clrscr();
printf(Enter your grade : );
scanf(%c,grade);
switch(grade)
{
case 'a':
printf(point = 80-100n);
break;
case 'b':
printf(point = 70-79n);
break;
case 'c':
printf(point = 60-69n);
break;
case 'd':
printf(point = 50-59n);
break;
case 'f':
printf(point = 0-49n);
break;
default :
printf(unknown);
}
getch();
}
Enter your grade : a
point = 80-100

11. -11-
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