Valmiki Ramayana Yuddha Kanda Sarga 42 Shloka 13
Original Shlokaप्रेक्षतोराक्षसेन्द्रस्यतान्यनीकानिभागशः । राघवप्रियकामार्थंलङ्कामारुरुहुस्तदा ।।6.42.13।।
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राक्षसेन्द्रस्य king of Rakshasas, प्रेक्षतो as he was looking, तान्यनीकानि all the Vanara army, राघवप्रियकामार्थं to make Rama happy, भागशः in divisions, लङ्काम Lanka, आरुरुहुस्तदा ascended the boundary.
To make Rama happy, all the Vanara army divided into groups and started ascending the boundary (of Lanka) walls the king of Rakshasas was witnessing.