foo.cc: In function 'int main()':
foo.cc:27:1: error: expected ';' before 'for'
 for(int i=ans[0];i>=1;i--)
 ^~~
foo.cc:27:17: warning: statement has no effect [-Wunused-value]
 for(int i=ans[0];i>=1;i--)
                 ^
foo.cc:27:18: error: 'i' was not declared in this scope
 for(int i=ans[0];i>=1;i--)
                  ^

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