57. State Machine Using Function Pointers

#include <stdio.h>

void state_init()    { printf("Init\n"); }
void state_load()    { printf("Load\n"); }
void state_execute() { printf("Execute\n"); }
void state_exit()    { printf("Exit\n"); }

void d() {state_init(); state_load(); state_execute();}

void a() { state_load(); state_execute(); state_exit();}

void c() { state_exit(); state_init(); state_load();}

void b() { state_execute(); state_exit(); state_init();} 

void (*fp[4]) () ={d, a, b, c};
void run_state_sequence(int start) {
    return fp[start]();
    // Implement using function pointer array
}

int main() {
    int start;
    scanf("%d", &start);
    run_state_sequence(start);
    return 0;
}