foo.cc: In function 'int main()':
foo.cc:6:24: warning: for increment expression has no effect [-Wunused-value]
    6 |         for(int i;i<N;i+1)
      |                       ~^~
foo.cc:8:18: warning: statement has no effect [-Wunused-value]
    8 |                 a+i;
      |                 ~^~
foo.cc:6:20: warning: 'i' is used uninitialized [-Wuninitialized]
    6 |         for(int i;i<N;i+1)
      |                   ~^~
foo.cc:6:17: note: 'i' was declared here
    6 |         for(int i;i<N;i+1)
      |                 ^
foo.cc:6:20: warning: 'N' is used uninitialized [-Wuninitialized]
    6 |         for(int i;i<N;i+1)
      |                   ~^~
foo.cc:5:13: note: 'N' was declared here
    5 |         int N,a;
      |             ^
foo.cc:10:15: warning: 'a' is used uninitialized [-Wuninitialized]
   10 |         cout<<a;
      |               ^
foo.cc:5:15: note: 'a' was declared here
    5 |         int N,a;
      |               ^

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