A题链接：https://codeforces.com/contest/1036/problem/A
A题AC代码：
1 #include <stdio.h> 2 #include <stdlib.h> 3 #include <string.h> 4 #include <math.h> 5 #include <malloc.h> 6 #include <stdbool.h> 7 #include <ctype.h> 8 9 typedef long long ll; 10 11 12 int main() 13 { 14 ll n, k, i, j, ans; 15 while( ~scanf( "%I64d%I64d", &n, &k ) ) 16 { 17 printf( "%I64d ", ( k + n - 1 ) / n ); 18 } 19 return 0; 20 }
B题链接：https://codeforces.com/contest/1036/problem/B
B题AC代码：
1 #include <iostream> 2 #include <cstring> 3 #include <cstdio> 4 5 typedef unsigned long long ULL; 6 typedef const int cint; 7 typedef long long LL; 8 using namespace std; 9 10 11 int q; 12 LL n,m,k; 13 template< typename Q > 14 void inin(Q &); 15 16 int main() 17 { 18 inin(q); 19 while( q -- ) 20 { 21 inin(n); 22 inin(m); 23 inin(k); 24 if( n > m ) 25 swap( n, m ); 26 if( k < m ) 27 printf( "-1" ); 28 else 29 { 30 if( n == m ) 31 { 32 if( ( k-n ) & 1 ) 33 printf( "%I64d", k - 2 ); 34 else 35 printf( "%I64d", k ); 36 } 37 else 38 { 39 LL temp = m - n; 40 if( temp & 1 ) 41 printf( "%I64d", k - 1 ); 42 else 43 { 44 if( ( k - m ) & 1 ) 45 printf( "%I64d", k - 2 ); 46 else 47 printf( "%I64d", k ); 48 } 49 } 50 } 51 printf( " " ); 52 } 53 return 0; 54 } 55 56 template< typename Q > 57 void inin( Q &x ) 58 { 59 x=0; 60 int f=0; 61 char ch; 62 scanf( "%c", &ch ); 63 while( ch < '0' || ch > '9' ) 64 { 65 if( ch == '-' ) 66 f = 1; 67 scanf( "%c", &ch ); 68 } 69 while( ch >= '0' && ch <= '9' ) 70 { 71 x = x*10 + ch - '0'; 72 scanf( "%c", &ch ); 73 } 74 x = f?-x:x; 75 }
C题链接：https://codeforces.com/contest/1036/problem/C
C题AC代码：
1 #include <stdio.h> 2 #include <stdlib.h> 3 #include <string.h> 4 #include <math.h> 5 #include <malloc.h> 6 #include <stdbool.h> 7 #include <ctype.h> 8 9 typedef long long ll; 10 11 ll Arr[20][4]; 12 int dig[20]; 13 ll dp( int, int, int ); 14 ll calc(ll); 15 16 int main() 17 { 18 memset( Arr, -1, sizeof(Arr) ); 19 int i, T=0; 20 ll L,R; 21 while( ~scanf( "%d", &T ) ) 22 { 23 for ( i = 1; i <= T; i ++ ) 24 { 25 scanf( "%I64d%I64d", &L, &R ); 26 L--; 27 printf( "%I64d ", calc(R) - calc(L) ); 28 } 29 } 30 return 0; 31 } 32 33 ll dp( int len, int res, int lim ) 34 { 35 if ( res > 3 ) 36 return 0; 37 if ( len == 0 ) 38 return 1; 39 if ( !lim && Arr[len][res] > 0 ) 40 return Arr[len][res]; 41 ll ret = 0; 42 int up = 9; 43 if (lim) 44 up=dig[len]; 45 int i; 46 for ( i = 0; i <= up; i ++ ) 47 ret += dp( len-1, res+(i>0), lim && ( i == up ) ); 48 if (!lim) Arr[len][res]=ret; 49 return ret; 50 } 51 52 ll calc(ll x) 53 { 54 int _sum = 0; 55 while (x) 56 { 57 dig[ ++ _sum ] = x % 10; 58 x /= 10; 59 } 60 return dp( _sum, 0, 1 ); 61 }
全部测过样例再提交，另外，本蒟蒻还从未做过D……
