foo.cc: In function 'int main()':
foo.cc:25:49: warning: statement has no effect [-Wunused-value]
   25 |                                 e[i] * l % q[j] == 1;
      |                                 ~~~~~~~~~~~~~~~~^~~~
foo.cc:26:41: warning: 'l' may be used uninitialized [-Wmaybe-uninitialized]
   26 |                                 cout << l;
      |                                         ^
foo.cc:4:52: note: 'l' was declared here
    4 |         int a, n, c, d, e[10000], q[100], o, p, i, l,j;//逆元l;
      |                                                    ^

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