typedef int Boolean;
#define TRUE 1
#define FALSE

struct data{
 float key;
 //...
};

Boolean sequential_search(struct data * V, int N, struct data target){
 Boolean found = FALSE;
 int count = 0;
 while(count<N && found==FALSE){
  if(V[count].key == target.key)
   found = TRUE;
  else
   count++;
  }
}