tavan.cpp: In function 'int main()':
tavan.cpp:12:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
scanf("%d%d%d%d", &n, &m, &k, &x);
~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~
tavan.cpp:13:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
scanf(" %s", a);
~~~~~^~~~~~~~~~
tavan.cpp:15:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
scanf(" %s", b[i]);
~~~~~^~~~~~~~~~~~~