foo.cc: In function 'int read()':
foo.cc:38:5: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
   38 |     for (; c >= '0' && c <= '9'; x = x * 10 + c - '0', c = NC()); x *= minus;
      |     ^~~
foo.cc:38:67: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'for'
   38 |     for (; c >= '0' && c <= '9'; x = x * 10 + c - '0', c = NC()); x *= minus;
      |                                                                   ^
foo.cc: In function 'double Check1(float)':
foo.cc:92:20: warning: suggest parentheses around assignment used as truth value [-Wparentheses]
   92 |         while(temp = Dfs(S, 32000)){
      |               ~~~~~^~~~~~~~~~~~~~~
foo.cc:89:25: warning: unused variable 's' [-Wunused-variable]
   89 |     double res = 0; int s = 0;
      |                         ^

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