This one works (once the simple compile-time errors have been fixed)! Ensure you understand the important difference between Example 21 and Example 19.

/* This programme finds the sum of two vectors and prints out the result. */ #include <stdio.h> int vecA[4] = {1,2,3,4}, vecB[4] = {90,91,92,93}; void vecadd(int *a1, *a2, *sum) { int i; for (i = 0; i < 4; i++) sum[i] = a1[i] + a2[i]; } main() { int ans[4]; int i; vecadd(vecA, vecB, ans); for (i = 0; i < 4; i++) printf("%d \n", ans[i]); }