import sys
n=int(input())
v=[0]*n
ans=""
for i in range (0, n):
    v[i]=int(input())
if(n==1):
    if(v[0] == 0):
        print("YES\n")
        sys.exit()
    else:
        print("NO\n")
        sys.exit()

vicIndex=n-1;
killIndex=vicIndex-1
for i in range (1, n+1):
    if(v[n-i] != 0):
        killIndex=n-i
        break
for i in range (0, n):
    if(v[killIndex]==0 or killIndex < 0 or killIndex >=vicIndex):
        break
    ans+=str(killIndex+1)
    ans+=" "
    ans+=str(vicIndex+1)
    ans+="\n"
    v[killIndex] = v[killIndex]-1
    if(v[killIndex] == 0):
        killIndex-=1
    if(v[vicIndex] != 0):
        b=0
    vicIndex-=1
b=1
for i in range (0, n):
    if(v[i] != 0):
        b=0
if(b==1):
    print("YES\n")
    print(ans)
else:
    print("NO\n")