Convert String to Integer

Code

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

int custom_atoi(const char *str) {
    int num = 0;
    int sign = 1;

    if(*str == '-'){
        sign = -1;
    }
    
    for(int i=0;*(str+i)!='\0';i++){
        
        char ch = *(str+i);
        if(ch=='+' || ch =='-'){
            continue;
        }
        if(ch>='0' && ch<='9'){
            num = num * 10 + (ch - '0');
        }
        else{
            break;
        }
        
    }
    return num*sign;
}

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;
}

Solving Approach