#include <stdio.h>

int ft_str_is_numeric(char *str) {
    while (*str) {
        if (*str < '0' || *str > '9') {
            return 0;
        }
        str++;
    }
    return 1;
}

int main() {
    char str1[] = "123";
    char str2[] = "12a";

    printf("%d\n", ft_str_is_numeric(str1));
    printf("%d\n", ft_str_is_numeric(str2));

    return 0;
}

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