Can't get my C program to print the output - c

Question

When I go to print the output of the program everything shows up as zero. I think the variable aren't storing themselves, but I'm not totally sure. When I go to look over everything, it looks right but clearly isn't. Any help would be really appreciated. Sorry if the formatting seems a little off, Stack Overflow wouldn't accept it otherwise.
#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
int digit(char term[])
{
int i = 0;
int val = 0;
while (term[i] != '\0')
{
val = val * 10 + term[i] - '0';
}
i++;
return val;
}
void error()
{
printf("Error: Sales figures must be numbers.\n");
printf("Please try again.\n");
}
bool isnumber(char term[])
{
int i = 0;
while (term[i])
{
if( isdigit(term[i]) == 0)
{
return false;
i++;
}
}
return true;
}
int main()
{
int sales[3][2], costs[3] = {3, 4, 1}, weekends[2] = {0, 0};
int i, j, val;
char term[100];
while (1)
{
printf("Number of Bagel sales on Saturday: ");
scanf("%s", term);
if( isnumber(term) == false)
{
error();
}
else
{
sales[0][0] = digit(term);
break;
}
}
while (1)
{
printf("Number of Flatbread sales on Saturday: ");
scanf("%s", term);
if( isnumber(term) == false)
{
error();
}
else
{
sales[1][0] = digit(term);
break;
}
}
while (1)
{
printf("Number of Muffin sales on Saturday: ");
scanf("%s", term);
if (isnumber(term) == false)
{
error();
}
else
{
sales[2][0] = digit(term);
break;
}
}
while (1)
{
printf("Number of Bagel sales on Sunday: ");
scanf("%s", term);
if( isnumber(term) == false)
{
error();
}
else
{
sales[0][1] = digit(term);
break;
}
}
while (1)
{
printf("Number of Flatbread sales on Sunday: ");
scanf("%s", term);
if( isnumber(term) == false)
{
error();
}
else
{
sales[1][1] = digit(term);
break;
}
}
while (1)
{
printf("Number of Muffin sales on Sunday: ");
scanf("%s", term);
if( isnumber(term) == false)
{
error();
}
else
{
sales[2][1] = digit(term);
break;
}
}
for (i = 0; i < 2, i++;)
{
for (j = 0; j < 3, j++;)
{
weekends[i] += costs[j] * sales[i][j];
}
}
printf("\n");
for (i = 0; i < 3, i++;)
{
printf("%d", costs[i]);
}
printf(".");
for (i = 0; i < 3, i++;)
{
for (j = 0; j < 2, j++;)
{
printf("%d", sales[i][j]);
}
if (i == 0)
{
printf(" = ");
printf("%d %d", weekends[0], weekends[1]);
}
printf("\n ");
}
printf("\nTotal sales on Saturday: $%d", weekends[0]);
printf("\nTotal sales on Sunday: $%d", weekends[1]);
printf("\nTotal sales over the weekend: $%d", weekends[0] + weekends[1]);
return 0;
}

Answer 1

You are not incrementing i in the loop. Your code for digit is:
int digit(char term[])
{
int i = 0;
int val = 0;
while (term[i] != '\0')
{
val = val * 10 + term[i] - '0';
}
i++; /* ---- this is outside the loop !! */
return val;
}
But it ought to look like:
int
digit(const char *term)
{
int val = 0;
while( *term != '\0' ){
val = val * 10 + *term - '0';
term += 1;
}
return val;
}