foo.cc: In function 'int main()':
foo.cc:26:2: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
   26 |  for(int k = 2; k <= n; k++)//枚举区间大小
      |  ^~~
foo.cc:51:3: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'for'
   51 |   printf("%d\n",f[1][n]);//很明显我们所求的是1—n区间
      |   ^~~~~~
foo.cc:18:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   18 |     scanf("%d",&n);
      |     ~~~~~^~~~~~~~~
foo.cc:21:11: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   21 |      scanf("%d",&v[i]);
      |      ~~~~~^~~~~~~~~~~~

Found 5 testcases.
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