Valmiki Ramayana Yuddha Kanda Sarga 30 Shloka 18
Original Shlokaतथात्रप्रतिपत्स्यामिज्ञात्वातेषांबलाबलम् । अवश्यंबलसङ् ख्यानंकर्तव्यंयुद्धमिच्छताम् ।।6.30.18।।
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तेषाम् their, बलाबलम् strength and weakness, ज्ञात्वा knowing, अत्र here, तथा likewise, प्रतिपत्स्यामि I would like to know what to do, युद्धम् war, इच्छताम् desiring, सङ् ख्यानम् their numbers, अवश्यम् essential, बल strength, कर्तव्यं it is essential.
"Likewise knowing their strengths and weaknesses from you I wish to know what to do. It is essential to know their numbers and strength before the war."