text: // File: fig0625.c
  // Computer Systems, Fifth edition
  // Figure 6.25
  
  #include <stdio.h>
  
  int binCoeff(int n, int k) {
     int y1, y2;
     if ((k == 0) || (n == k)) {
        return 1;
     }
     else {
        y1 = binCoeff(n - 1, k); // ra2
        y2 = binCoeff(n - 1, k - 1); // ra3
        return y1 + y2;
     }
  }
  
  int main() {
     printf("binCoeff(3, 1) = %d\n", binCoeff(3, 1)); // ra1
     return 0;
  }
  