package main

import (
	"fmt"
)

func main() {
	var n, m, k int
	if _, err := fmt.Scan(&n, &m, &k); err != nil {
		return
	}

	dp2 := make([]int, k)
	for i := range dp2 {
		dp2[i] = -1
	}
	dp2[0] = 0

	half := m / 2

	for r := 0; r < n; r++ {
		dp1 := make([][]int, half+1)
		for i := range dp1 {
			dp1[i] = make([]int, k)
			for j := range dp1[i] {
				dp1[i][j] = -1
			}
		}
		dp1[0][0] = 0

		for c := 0; c < m; c++ {
			var x int
			fmt.Scan(&x)
			for i := half - 1; i >= 0; i-- {
				for j := 0; j < k; j++ {
					if dp1[i][j] != -1 {
						val := dp1[i][j] + x
						rem := val % k
						if val > dp1[i+1][rem] {
							dp1[i+1][rem] = val
						}
					}
				}
			}
		}

		rowMax := make([]int, k)
		for i := range rowMax {
			rowMax[i] = -1
		}
		for i := 0; i <= half; i++ {
			for j := 0; j < k; j++ {
				if dp1[i][j] > rowMax[j] {
					rowMax[j] = dp1[i][j]
				}
			}
		}

		ndp2 := make([]int, k)
		for i := range ndp2 {
			ndp2[i] = -1
		}

		for u := 0; u < k; u++ {
			if dp2[u] != -1 {
				for v := 0; v < k; v++ {
					if rowMax[v] != -1 {
						val := dp2[u] + rowMax[v]
						rem := val % k
						if val > ndp2[rem] {
							ndp2[rem] = val
						}
					}
				}
			}
		}
		dp2 = ndp2
	}

	fmt.Println(dp2[0])
}