N = int(input())
etelek = []
for i in range(N):
sz, m = (int(x) for x in input().split())
if m < 4:
continue
etelek.append((i + 1, sz, m >= 5))
etelek.sort(key=lambda x: x[1])
e4 = []
e5 = []
for i, sz, m in etelek:
if m and len(e5) < sz:
e5.append(i)
elif len(e4) < sz:
e4.append(i)
while len(e5) > len(e4):
e4.append(e5.pop())
print(len(e5))
for i in range(len(e5)):
print(e4[i], e5[i])
| Subtask | Sum | Test | Verdict | Time | Memory | ||
|---|---|---|---|---|---|---|---|
| subtask1 | 0/0 | ||||||
| 1 | Accepted | 14ms | 3124 KiB | ||||
| subtask2 | 10/10 | ||||||
| 2 | Accepted | 17ms | 3308 KiB | ||||
| 3 | Accepted | 16ms | 3116 KiB | ||||
| 4 | Accepted | 17ms | 3120 KiB | ||||
| 5 | Accepted | 17ms | 3124 KiB | ||||
| 6 | Accepted | 16ms | 3124 KiB | ||||
| 7 | Accepted | 16ms | 3124 KiB | ||||
| 8 | Accepted | 16ms | 2948 KiB | ||||
| 9 | Accepted | 17ms | 3124 KiB | ||||
| 10 | Accepted | 17ms | 2988 KiB | ||||
| 11 | Accepted | 17ms | 2980 KiB | ||||
| subtask3 | 20/20 | ||||||
| 12 | Accepted | 16ms | 3316 KiB | ||||
| 13 | Accepted | 16ms | 3036 KiB | ||||
| 14 | Accepted | 16ms | 3124 KiB | ||||
| 15 | Accepted | 16ms | 3144 KiB | ||||
| 16 | Accepted | 16ms | 2988 KiB | ||||
| 17 | Accepted | 17ms | 3064 KiB | ||||
| 18 | Accepted | 17ms | 3180 KiB | ||||
| 19 | Accepted | 16ms | 2984 KiB | ||||
| 20 | Accepted | 17ms | 3148 KiB | ||||
| 21 | Accepted | 17ms | 3124 KiB | ||||
| 22 | Accepted | 17ms | 3124 KiB | ||||
| 23 | Accepted | 18ms | 3136 KiB | ||||
| 24 | Accepted | 19ms | 3264 KiB | ||||
| 25 | Accepted | 17ms | 3244 KiB | ||||
| 26 | Accepted | 17ms | 3124 KiB | ||||
| 27 | Accepted | 20ms | 3360 KiB | ||||
| 28 | Accepted | 21ms | 3196 KiB | ||||
| 29 | Accepted | 17ms | 3208 KiB | ||||
| 30 | Accepted | 18ms | 3124 KiB | ||||
| 31 | Accepted | 18ms | 3144 KiB | ||||
| subtask4 | 15/15 | ||||||
| 32 | Accepted | 16ms | 3324 KiB | ||||
| 33 | Accepted | 16ms | 3140 KiB | ||||
| 34 | Accepted | 16ms | 3104 KiB | ||||
| 35 | Accepted | 17ms | 3144 KiB | ||||
| 36 | Accepted | 17ms | 2976 KiB | ||||
| 37 | Accepted | 17ms | 3144 KiB | ||||
| 38 | Accepted | 17ms | 3076 KiB | ||||
| 39 | Accepted | 16ms | 2924 KiB | ||||
| 40 | Accepted | 17ms | 3120 KiB | ||||
| 41 | Accepted | 19ms | 3160 KiB | ||||
| 42 | Accepted | 17ms | 3140 KiB | ||||
| 43 | Accepted | 19ms | 3316 KiB | ||||
| 44 | Accepted | 16ms | 3124 KiB | ||||
| 45 | Accepted | 17ms | 3404 KiB | ||||
| 46 | Accepted | 21ms | 3192 KiB | ||||
| subtask5 | 15/15 | ||||||
| 47 | Accepted | 17ms | 3124 KiB | ||||
| 48 | Accepted | 17ms | 3324 KiB | ||||
| 49 | Accepted | 17ms | 3312 KiB | ||||
| 50 | Accepted | 17ms | 3320 KiB | ||||
| 51 | Accepted | 17ms | 3176 KiB | ||||
| 52 | Accepted | 17ms | 3284 KiB | ||||
| 53 | Accepted | 17ms | 3328 KiB | ||||
| 54 | Accepted | 17ms | 3316 KiB | ||||
| 55 | Accepted | 16ms | 3108 KiB | ||||
| 56 | Accepted | 17ms | 3320 KiB | ||||
| 57 | Accepted | 17ms | 3120 KiB | ||||
| 58 | Accepted | 16ms | 3132 KiB | ||||
| 59 | Accepted | 17ms | 3112 KiB | ||||
| 60 | Accepted | 16ms | 3076 KiB | ||||
| 61 | Accepted | 16ms | 3124 KiB | ||||
| subtask6 | 15/15 | ||||||
| 62 | Accepted | 17ms | 3124 KiB | ||||
| 63 | Accepted | 17ms | 3320 KiB | ||||
| 64 | Accepted | 20ms | 3420 KiB | ||||
| 65 | Accepted | 20ms | 3380 KiB | ||||
| 66 | Accepted | 21ms | 3380 KiB | ||||
| 67 | Accepted | 17ms | 3352 KiB | ||||
| 68 | Accepted | 17ms | 3220 KiB | ||||
| 69 | Accepted | 17ms | 3164 KiB | ||||
| 70 | Accepted | 17ms | 3124 KiB | ||||
| 71 | Accepted | 19ms | 3124 KiB | ||||
| 72 | Accepted | 17ms | 3124 KiB | ||||
| 73 | Accepted | 18ms | 3124 KiB | ||||
| 74 | Accepted | 18ms | 3124 KiB | ||||
| 75 | Accepted | 17ms | 3124 KiB | ||||
| 76 | Accepted | 16ms | 3136 KiB | ||||