Ranged or melee weapons based on player radius

/scoreboard objectives add timer dummy
/scoreboard players add @a timer 1
/scoreboard players set @a[score_timer_min=60] timer 0
/execute @a ~ ~ ~ /replaceitem entity @e[type=Skeleton,r=4] slot.weapon iron_sword
/execute @a[score_timer_min=60] ~ ~ ~ /replaceitem entity @e[type=Skeleton,r=50,rm=4] slot.weapon bow