可以在case中更改switch变量吗？

#include <stdio.h>

int main() {
    int num = 2;
    
    switch (num) {
        case 1:
            printf("num is 1\n");
            break;
        case 2:
            printf("num is 2\n");
            num = 3;  // 在case中修改switch变量
            break;
        case 3:
            printf("num is 3\n");
            break;
        default:
            printf("num is not 1, 2, or 3\n");
            break;
    }
    
    printf("Modified num: %d\n", num);
    
    return 0;
}

num is 2
Modified num: 3