foo.cc: In function 'int main()':
foo.cc:7:24: warning: for increment expression has no effect [-Wunused-value]
    7 |  for(int i=100;i<=100;i<=999;i++)
      |                       ~^~~~~
foo.cc:7:29: error: expected ')' before ';' token
    7 |  for(int i=100;i<=100;i<=999;i++)
      |     ~                       ^
      |                             )
foo.cc:7:2: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
    7 |  for(int i=100;i<=100;i<=999;i++)
      |  ^~~
foo.cc:7:30: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'for'
    7 |  for(int i=100;i<=100;i<=999;i++)
      |                              ^
foo.cc:7:30: error: 'i' was not declared in this scope
foo.cc:6:6: warning: unused variable 'k' [-Wunused-variable]
    6 |  int k=0;
      |      ^

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