foo.cc: In function 'double cal(ll, ll)':
foo.cc:35:17: warning: suggest parentheses around arithmetic in operand of '^' [-Wparentheses]
     return (dp[r&1^1][k]-(sum[k]*sum[k])-dp[r&1^1][j]+(sum[j]*sum[j]))*1.0/(sum[j]-sum[k]);
                ~^~
foo.cc:35:46: warning: suggest parentheses around arithmetic in operand of '^' [-Wparentheses]
     return (dp[r&1^1][k]-(sum[k]*sum[k])-dp[r&1^1][j]+(sum[j]*sum[j]))*1.0/(sum[j]-sum[k]);
                                             ~^~
foo.cc: In function 'int main()':
foo.cc:57:28: warning: suggest parentheses around arithmetic in operand of '^' [-Wparentheses]
             dp[r&1][i]=dp[r&1^1][q[h]]+sum[q[h]]*(sum[i]-sum[q[h]]);
                           ~^~

自豪的采用jd5进行评测(github.com/masnn/jd5)

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