#include <stdio.h>

int main() {
     
        printf("     **\n");
        printf("     **\n");
        printf("************\n");
        printf("************\n");
        printf("    *  *\n");
        printf("    *  *\n"); 
    return 0;
}

正确:

printf(" **\n");

printf(" **\n");

printf("************\n");

printf("************\n");

printf(" * *\n");

printf(" * *\n");

错误:

printf("**\n");

printf("**\n");

printf("************\n");

printf("************\n");

printf("* *\n");

printf("* *\n");