foo.cc: In function 'int main()':
foo.cc:15:36: warning: suggest parentheses around '-' inside '<<' [-Wparentheses]
   15 |  for (int i = 1;i <= n;++ i) f[1<<i-1][i] = 0;
      |                                   ~^~
foo.cc:18:16: warning: suggest parentheses around '-' inside '>>' [-Wparentheses]
   18 |    if (((i >> j-1) & 1) == 1) {
      |               ~^~
foo.cc:20:19: warning: suggest parentheses around '-' inside '>>' [-Wparentheses]
   20 |      if (((i >> k - 1) & 1) == 0) {
      |                 ~~^~~
foo.cc:21:16: warning: suggest parentheses around '-' inside '<<' [-Wparentheses]
   21 |       f[i|(1<<k-1)][k] = min(f[i][j] + a[j][k], f[i|(1<<k-1)][k]);
      |               ~^~
foo.cc:21:58: warning: suggest parentheses around '-' inside '<<' [-Wparentheses]
   21 |       f[i|(1<<k-1)][k] = min(f[i][j] + a[j][k], f[i|(1<<k-1)][k]);
      |                                                         ~^~
foo.cc:8:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
    8 |  scanf ("%d",&n);
      |  ~~~~~~^~~~~~~~~
foo.cc:11:9: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   11 |    scanf("%d",&a[i][j]);
      |    ~~~~~^~~~~~~~~~~~~~~

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