C语言求两个数组的交集

以下是两个数组的交集的C语言代码：

#include <stdio.h>

int main() {
    int arr1[] = {1, 2, 3, 4, 5};
    int arr2[] = {3, 5, 7, 9};
    int size1 = sizeof(arr1) / sizeof(arr1[0]);
    int size2 = sizeof(arr2) / sizeof(arr2[0]);
    int intersection[size1]; // 交集数组
    int count = 0; // 交集数量

    // 遍历arr1
    for (int i = 0; i < size1; i++) {
        int found = 0; // 是否已找到该元素
        // 遍历arr2，寻找相等的元素
        for (int j = 0; j < size2; j++) {
            if (arr1[i] == arr2[j]) {
                found = 1;
                break;
            }
        }
        if (found) {
            intersection[count++] = arr1[i]; // 将该元素添加到交集数组中
        }
    }

    // 输出交集
    printf("Intersection: ");
    for (int i = 0; i < count; i++) {
        printf("%d ", intersection[i]);
    }
    printf("\n");

    return 0;
}

输出：

Intersection: 3 5