conflicting type / previous declariation ___ was here

[Thaox]

#define TRIP 6
#include <stdio.h>

char error_area(char area_code, char S, char M, char L,char N,char P, char K, char R, char C, char U, char W, char O, char T, char F);

int main(void)
{


char area_code, S, M, L, N, P, K, R, C, U, W, O, T, F, checkB;
char travelarea[TRIP];

printf("Please select from the following that best describes your destination:\n"); /*area code input*/
printf("S Small city - population under 50,000\n"); /*Choices for area code*/
printf("M Medium city - population between 50,000 and 500,000\n");
printf("L Large city - pop. over 500,000\n");
printf("N Natural formation like a mountain, a lake, a cave, a geyser, a fjord, a canyon, etc.\n");
printf("P Designated park or reserve such as a wildlife refuge, a national park, a bioreserve, or a protected marine area\n");
printf("K Man made landmark like the Great Wall of China, the Taj Mahal, or Stonehenge\n");
printf("R State or province or region of a country\n");
printf("C Whole country\n");
printf("U Multiple countries like traveling through Europe\n");
printf("W Ocean voyage\n");
printf("O Any other type of destination - such as visiting the sites of the seven wonders of the world\n");
printf("Please enter the Area Letter code:");
scanf(" %c", &area_code);
travelarea[i]=area_code;




checkB = error_area(area_code, S, M, L, N, P, K, R, C, U, W, O, T, F);
while (checkB == F) /*error loop for error area code*/
{
printf("Please re-enter a valid area_code:");
scanf("% c", &area_code);
checkB = error_area(area_code, S, M, L, N, P, K, R, C, U, W, O, T, F);
if (checkB == T)
{travelarea[i]=area_code;}
}

error_area(area_code, S, M, L, N, P, K, R, C, U, W, O, Z, T, F) /*area code error check*/
{

if ( (area_code == S) || (area_code == M) || (area_code == L) ||(area_code == N) ||(area_code == P) ||(area_code == K) || (area_code == R) ||(area_code == C) || (area_code == U) || (area_code == W) || (area_code == O))
{
return T;
}
else
{
printf("Area code is invalid. (Please make sure code is caplitalize)\n");

return F ;
}
}
I keep getting these area
test2.c:46: error: conflicting types for âerror_areaâ
test2.c:5: error: previous declaration of âerror_areaâ was here
I'm not sure why, I've been going through it and maybe its just I'm not seeing it ( this is C)

[hazel]

In your function declaration, you specify the return type as char. In the function definition below, you don't specify the return type so the compiler assumes the default type: int. Hence the conflict.

[Rubberman]

Hazel, I LOVE your so succinct and to-the-point answers! Great stuff!