7 Segment Display using Arduino

//Code:

int a=13;
int b=12;
int c=11;
int d=10;
int e=9;
int f=8;
int g=7;

void setup()
{
pinMode(a,OUTPUT);
pinMode(b,OUTPUT);
pinMode(c,OUTPUT);
pinMode(d,OUTPUT);
pinMode(e,OUTPUT);
pinMode(f,OUTPUT);
pinMode(g,OUTPUT);

}

void loop() {
//for 0:
digitalWrite (a,1);
digitalWrite (b,1);
digitalWrite (c,1);
digitalWrite (d,1);
digitalWrite (e,1);
digitalWrite (f,1);
digitalWrite (g,0);
delay (600);

//for 1:
digitalWrite (a,0);
digitalWrite (b,1);
digitalWrite (c,1);
digitalWrite (d,0);
digitalWrite (e,0);
digitalWrite (f,0);
digitalWrite (g,0);
delay (600);

//for 2:
digitalWrite (a,1);
digitalWrite (b,1);
digitalWrite (c,0);
digitalWrite (d,1);
digitalWrite (e,1);
digitalWrite (f,0);
digitalWrite (g,1);
delay (600);

//for 3 CS:
digitalWrite (a,1);
digitalWrite (b,1);
digitalWrite (c,1);
digitalWrite (d,1);
digitalWrite (e,0);
digitalWrite (f,0);
digitalWrite (g,1);
delay (600);

//for 4:
digitalWrite (a,0);
digitalWrite (b,1);
digitalWrite (c,1);
digitalWrite (d,0);
digitalWrite (e,0);
digitalWrite (f,1);
digitalWrite (g,1);
delay (600);

//for 5:
digitalWrite (a,1);
digitalWrite (b,0);
digitalWrite (c,1);
digitalWrite (d,1);
digitalWrite (e,0);
digitalWrite (f,1);
digitalWrite (g,1);
delay (600);

//for 6:
digitalWrite (a,1);
digitalWrite (b,0);
digitalWrite (c,1);
digitalWrite (d,1);
digitalWrite (e,1);
digitalWrite (f,1);
digitalWrite (g,1);
delay (600);

//for 7
digitalWrite (a,1);
digitalWrite (b,1);
digitalWrite (c,1);
digitalWrite (d,0);
digitalWrite (e,0);
digitalWrite (f,0);
digitalWrite (g,0);
delay (600);

//for 8:
digitalWrite (a,1);
digitalWrite (b,1);
digitalWrite (c,1);
digitalWrite (d,1);
digitalWrite (e,1);
digitalWrite (f,1);
digitalWrite (g,1);
delay (600);

//for 9:
digitalWrite (a,1);
digitalWrite (b,1);
digitalWrite (c,1);
digitalWrite (d,1);
digitalWrite (e,0);
digitalWrite (f,1);
digitalWrite (g,1);
delay (600);
}