#include <stdio.h>
void main ( ) 
{
int y1, x1, y2, x2, m;
char answer;
printf("please enter y1, x1, y2, x2\n")
printf("y1:");
scanf("%d\n",&y1);
printf("x1:");
scanf("%d\n",&x1);
printf("y2:");
scanf("%d\n",&y2);
printf("x2:");
scanf("%d\n",&x2);
printf("y1:%d\n x1:%d\n y2:%d\n x2:%d\n",y1,x1,y2,x2);
printf("are u sure?(yes/no)");
scanf("%c\n",&anser);
if (anser==yes)
{
m=(y2-y1)/(x2-x1);
printf("M=%d",m);
printf("thanks for using the sofware");
}
else if (anser==no)
{
printf("pliz enter again y1, x1, y2, x2\n");
printf("y1:");
scanf("%d\n",&y1);
printf("x1:");
scanf("%d\n",&x1);
printf("y2:");
scanf("%d\n",&y2);
printf("x2:");
scanf("%d\n",&x2);
m=(y2-y1)/(x2-x1);
printf("M=%d",m);
printf("thanks for using the sofware");
}
else
   printf("the anser is ERROR");
}

char word;
word="ROTTER"

word="R"

char word;
word="ROTTER"

if (word=="ROTTER")
   printf("ROTTER RULZ\n");
 זה במקרה של פקודה אחת!
if (word=="ROTTER")
{
 printf("ROTTER RULZ\n");
 scanf("%d",&a);
}
וזה במקרה של שני פקודות ויותר!