C语言实现输入一个字符串，把该字符串中的正整数数字提取出来，保存到一个int num[N]数组里并打印

#include <stdio.h>
#include <ctype.h>
#define N 100

int main() {
    char str[N];
    int num[N], count = 0;
    printf("请输入一个字符串:\n");
    fgets(str, N, stdin);

    for (int i = 0; str[i] != '\0'; i++) {
        if (isdigit(str[i])) {
            int n = str[i] - '0';
            i++;
            while (isdigit(str[i])) {
                n = n * 10 + (str[i] - '0');
                i++;
            }
            num[count++] = n;
        }
    }

    printf("提取出的数字为:");
    for (int i = 0; i < count; i++) {
        printf("%d ", num[i]);
    }
    printf("\n");

    return 0;
}