检查字符串中是否存在子字符串

const str = "Hello, World!";
const substring = "World";
if (str.includes(substring)) {
    console.log("Substring found!");
} else {
    console.log("Substring not found!");
}

import re

string = "Hello, World!"
substring = "World"
if re.search(substring, string):
    print("Substring found!")
else:
    print("Substring not found!")

#include <stdio.h>
#include <stdbool.h>

bool checkSubstring(const char* string, const char* substring) {
    while (*string) {
        const char* p1 = string;
        const char* p2 = substring;
        while (*p1 && *p2 && *p1 == *p2) {
            p1++;
            p2++;
        }
        if (!*p2) {
            return true;  // Substring found
        }
        string++;
    }
    return false;  // Substring not found
}

int main() {
    const char* str = "Hello, World!";
    const char* sub = "World";
    if (checkSubstring(str, sub)) {
        printf("Substring found!\n");
    } else {
        printf("Substring not found!\n");
    }
    return 0;
}