Difference between time(0) and clock() in CPP and C?

The main difference between time and clock in CPP and C is what is counted!

1.) ... The time(0) or time(&timer);
2.) ... The return value of clock()! 

1.) The time(0) or time(&timer);

2.) The return value of clock()! 

#include <stdio.h>
#include <time.h>
 
int main() 
{
 clock_t start_t, end_t;
 double total_time;
 int i = 0;
 
 // Record the start time
 start_t = clock();
 printf("Scanning large loop, start_t = %ld\n", start_t);
 
 // Execute the loop
 for (i = 0; i < 10000000; i++) {
  // Insert code for your loop here
 }
 
 // Record the end time
 end_t = clock();
 printf("End of large loop, end_t = %ld\n", end_t);
 
 // Calculate the total execution time
 total_time = (double)(end_t - start_t) / CLOCKS_PER_SEC;
 printf("Total time: %f seconds\n", total_time);
 
 return 0;
}