foo.cc: In function 'int main()':
foo.cc:7:1: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
    7 | for(i=0;i<=len;i++)a[i]=1;while(m--){cin>>j>>k;for(i=j;i<=k;i++)a[i]=0;}
      | ^~~
foo.cc:7:27: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'for'
    7 | for(i=0;i<=len;i++)a[i]=1;while(m--){cin>>j>>k;for(i=j;i<=k;i++)a[i]=0;}
      |                           ^~~~~

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