Variable declared and initialized in a switch statement

Question

Why does this program not output 20?

#include<stdio.h>

int main() {
    int a = 1;
    switch (a) {
            int b = 20;
        case 1:
        {
            printf("b is %d\n", b);
            break;
        }
        default:
        {
            printf("b is %d\n", b);
            break;
        }
    }
    return 0;
}

Answer 1

Because the switch statement jumps to a relevant case, so the line int b = 20 will never be executed.