/in/foo.c: In function 'main':
/in/foo.c:5:30: warning: unused variable 'xunhuan' [-Wunused-variable]
  int x, y, n, c, d, i, j, l, xunhuan, a[101] = { 0 }, b[101] = { 0 };
                              ^~~~~~~
/in/foo.c:36:10: warning: 'd' may be used uninitialized in this function [-Wmaybe-uninitialized]
    if (d == i && c == 1) { printf ( "("); printf("%d",a[i]); }
        ~~^~~~