Re: [問題] 數數字

作者: DreamYeh (天使)   2020-01-01 17:13:40
※ 引述《ACGfans (ACGfans)》之銘言:
: 從 1 數到 n (n > 1)
: 1 這個數字出現的次數剛好為 n
: Q1 : n 最小為何?
: Q2 : n 最大為何?
這題想了半天感覺只能用程式跑
最小為 199981
最大為 1111111110 但可能無上限,
以下為程式碼
int main()
{
unsigned int i, j, num = 0;
for(i=1;i<4294967295;i++) {
for(j=i;j!=0;j/=10) {
if (j%10 == 1) num++;
}
if(i==num) printf("the same! i=%d \n", i);
}
printf("end1\n");
return 0;
}
Result:
the same! i=1
the same! i=199981
the same! i=199982
the same! i=199983
the same! i=199984
the same! i=199985
the same! i=199986
the same! i=199987
the same! i=199988
the same! i=199989
the same! i=199990
the same! i=200000
the same! i=200001
the same! i=1599981
the same! i=1599982
the same! i=1599983
the same! i=1599984
the same! i=1599985
the same! i=1599986
the same! i=1599987
the same! i=1599988
the same! i=1599989
the same! i=1599990
the same! i=2600000
the same! i=2600001
the same! i=13199998
the same! i=35000000
the same! i=35000001
the same! i=35199981
the same! i=35199982
the same! i=35199983
the same! i=35199984
the same! i=35199985
the same! i=35199986
the same! i=35199987
the same! i=35199988
the same! i=35199989
the same! i=35199990
the same! i=35200000
the same! i=35200001
the same! i=117463825
the same! i=500000000
the same! i=500000001
the same! i=500199981
the same! i=500199982
the same! i=500199983
the same! i=500199984
the same! i=500199985
the same! i=500199986
the same! i=500199987
the same! i=500199988
the same! i=500199989
the same! i=500199990
the same! i=500200000
the same! i=500200001
the same! i=501599981
the same! i=501599982
the same! i=501599983
the same! i=501599984
the same! i=501599985
the same! i=501599986
the same! i=501599987
the same! i=501599988
the same! i=501599989
the same! i=501599990
the same! i=502600000
the same! i=502600001
the same! i=513199998
the same! i=535000000
the same! i=535000001
the same! i=535199981
the same! i=535199982
the same! i=535199983
the same! i=535199984
the same! i=535199985
the same! i=535199986
the same! i=535199987
the same! i=535199988
the same! i=535199989
the same! i=535199990
the same! i=535200000
the same! i=535200001
the same! i=1111111110
作者: LPH66 (-6.2598534e+18f)   2020-01-01 20:04:00
都跑出來了就來給個 https://oeis.org/A014778
作者: cutekid (可愛小孩子)   2020-01-01 21:34:00
推推(Y)
作者: ACGfans (菜心)   2020-01-02 16:14:00
正解 上限就是這樣了 n越大會差距越多

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