Infinite loop due to wrong condition in C - c

Question

Hey guys i'm new to C and i'm trying to learn something by myself.
So here's the question: i have an infinite loop and i don't understand why.
I've already checked other topics but i didn't understand, actually.
Here's the code:
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
/**
* Auto-generated code below aims at helping you parse
* the standard input according to the problem statement.
**/
int main()
{
int n,i=0; // the number of temperatures to analyse
scanf("%d", &n); fgetc(stdin);
char temps[257]; // the n temperatures expressed as integers ranging from -273 to 5526
fgets(temps, 257, stdin); // the n temperatures expressed as integers ranging from -273 to 5526
int temp[257]={0};
char *pointer;
pointer= temps;
while(*pointer != NULL){
int i=0, sign=1;
if(*pointer == '-'){
sign=-1;
pointer++;
}
while(*pointer != 32) { //infinite loop!
if(*pointer >='0' && *pointer<='9'){
temp[i]= (temp[i] *10) + ((*pointer) -'0');
temp[i]= temp[i]*sign;
printf("try");
}
}
printf("%d\n", temp[i]); //verifying temps != 0
pointer++;
i++;
}
return 0;
}
I really don't understand why.
Anyway, the aim of the program is: "Write a program that prints the temperature closest to 0 among input data. If two numbers are equally close to zero, positive integer has to be considered closest to zero (for instance, if the temperatures are -5 and 5, then display 5)."
You may need it.
Thank you in advance.

Answer 1

In the loop:
while(*pointer != 32)
you never change pointer or *pointer within the loop body. So if this loop is entered once then it can never exit.
You probably meant to have a pointer++ somewhere, and perhaps the loop condition should actually be while(*pointer >='0' && *pointer<='9') (what if the string has some numbers, then a letter, then some numbers?)
However bear in mind that this loop will also have to check for end-of-string ('\0') and exit the outer loop correctly if it does hit that (instead of doing pointer++ and going past the terminator as you do in the case of the input being just -).

Answer 2

Ok, I actually understood. Thank you.
So now this is the loop
while(*pointer != 32 || *pointer != '\0') {
if(*pointer >='0' && *pointer<='9'){
temp[i]= (temp[i] *10) + ((*pointer) -'0');
temp[i]= temp[i]*sign;
pointer++;
}
}
Now it gives me values, but at a certain point, it becomes infinite.
The rest of the code is the same.
EDIT: i modified the loop condition with while(*pointer >='0' && *pointer<='9') and it's not infinite!
But doesn't work. There may be a logical mistake.
EDIT 2: i found it. i've initialized i=0 in the while loop and of course it kept updating the same temp[i].
Thank you again.