Thread: urgent help needed with itoa

If I test below code, it throws errors. I am not sure why these errors are coming here?
Where are these multiple definitions for itoa, main and reverse?

Code:

#include <stdio.h>
#include <stdbool.h>
 
void reverse(char output[], int len)
{
   int start, end;
   char temp;
   for(start=0, end=len-1; start < end; start++, end--) {
      temp = *(output+start);
      *(output+start) = *(output+end);
      *(output+end) = temp;
   }
}
 
void itoa (int input, char* output, int rad){
   int i = 0;
   bool isnegative = false;
 
   if(input == 0) {
      output[i] = '0';
      output[i + 1] = '\0';
   }
 
   if(input < 0 && rad == 10){
      isnegative = true; // NOT bool isnegative = true;
      input = -input;
   }
 
   while (input != 0){
      int rem = input%rad;
      output[i++] = (rem > 9) ? (rem-10) + 'A' : rem + '0';
      input = input/rad;
   }
 
   if(isnegative){
      output[i++] = '-';
   }
 
   output[i] = '\0';
   reverse(output, i);
}
 
 
int main (){
 
   int i, b;
   char array[148];
   printf("Enter a number and base\n");
   scanf("%d %d", &i, &b);
 
   itoa(i, array, b);
   printf("String : %s\n", array);
 
   return 0;
}

OUTPUT: 
main.c:(.text+0x0): multiple definition of `reverse'; /tmp/ccPlW4oc.o:main.c:(.text+0x0): first defined here
/usr/bin/ld: /tmp/ccAtpqk9.o: in function `itoa':
main.c:(.text+0x7a): multiple definition of `itoa'; /tmp/ccPlW4oc.o:main.c:(.text+0x7a): first defined here
/usr/bin/ld: /tmp/ccAtpqk9.o: in function `main':
main.c:(.text+0x160)  : multiple definition of `main'; /tmp/ccPlW4oc.o:main.c:(.text+0x160): first defined here
collect2: error: ld returned 1 exit status