AC

import sys
n=int(input())
#v=[0]*n
ans=''
v = [int(x) for x in input().split(' ')]
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')