Convert String to Integer

#include <stdio.h>
#include <stdint.h>

int custom_atoi(const char *str) {
    // Your logic here
    int i=0;
    int num=0;
    int ch=1;

    if(str[0]=='-'||str[0]=='+'||(str[0]>='0'&&str[0]<='9')){
       if(str[0]=='-'){
        ch=-1;
        i++;
       }
       else if(str[0]=='+'){
        ch=1;
        i++;
       }
       while(str[i]>='0'&&str[i]<='9'&&str[i]!='\0'){
        num=num*10+(str[i]-'0');
        i++;
       }
       return ch*num;
    }
            
        
 return 0;
    
}

int main() {
    char str[101];
    fgets(str, sizeof(str), stdin);

    // Remove newline
    uint8_t i = 0;
    while (str[i]) {
        if (str[i] == '\n') {
            str[i] = '\0';
            break;
        }
        i++;
    }

    printf("%d", custom_atoi(str));
    return 0;
}