3286:How many 0's?
keyword
整数 10進数 C++
概要
2282:The Counting Problemの文字0のみに関する問題。
int64 get(int64 n){ if(n<0) return 0; int64 ret = 1; int64 d = 1; int64 accum = 1; while(n){ int r = n%10; if(!r) ret += accum; else ret += d; accum += d*r; n /= 10; ret += (n-1)*d; d *= 10; } return ret; } int main(){ int64 m, n; while(m = readint(), n = readint(), m>=0){ printf("%lld\n",get(n)-get(m-1)); } return 0; }