try yourself |run program

#include <stdio.h> 
#include <conio.h> 

int s;
void getDataByPara(int a, int b, int c=0, int d=0){
  s = a + b + c + d;
 printf("\n sum = %d",s);
}

void main(){
 clrscr();
 printf("\n This is parameterize function program.");
 getDataByPara(10, 20, 30); /* 10, 20, 30 goes to a, b, c respectively. */
 getch();
}

Program Output

This is parameterize function program.
sum = 60