C :

#include<stdio.h>

int main()
{
	int a,b,c;
	a=1;
	b=2;
	c=a+b;
	printf("%d",c);
}

C++ :

#include<stdio.h>

int main()
{
int a,b,c;
a=1;
b=2;
c=a+b;
printf("%d",c);
	return 0;
}

Pascal :

begin
  writeln(1+2);
end.