foo.cc: In function 'int main()':
foo.cc:20:23: warning: comparison of integer expressions of different signedness: 'int' and 'size_t' {aka 'long unsigned int'} [-Wsign-compare]
   20 |         for(int i=0; i<strlen(a[1]); i++)
      |                      ~^~~~~~~~~~~~~
foo.cc:27:40: warning: comparison of integer expressions of different signedness: 'int' and 'size_t' {aka 'long unsigned int'} [-Wsign-compare]
   27 |                         for (int j=0; j<strlen(a[i]); j++)
      |                                       ~^~~~~~~~~~~~~
foo.cc:34:48: warning: comparison of integer expressions of different signedness: 'int' and 'size_t' {aka 'long unsigned int'} [-Wsign-compare]
   34 |                                 for (int j=0; j<strlen(st[top]); j++)
      |                                               ~^~~~~~~~~~~~~~~~
foo.cc:39:39: warning: comparison of integer expressions of different signedness: 'int' and 'size_t' {aka 'long unsigned int'} [-Wsign-compare]
   39 |                         for(int j=0; j<strlen(a[i]); j++)
      |                                      ~^~~~~~~~~~~~~

正在同步测试数据，请稍后
Found 5 testcases.
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