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最新推荐文章于 2025-02-20 01:00:00 发布

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最新推荐文章于 2025-02-20 01:00:00 发布

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分类专栏： TC 总结文章标签： string less

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D1D2的250p都是水题，特别纯净的那种。

D1 500p HexatridecimalSum

高精度模板上吧！

D1 1000p IncreasingLists

花了半个下午搞定。首先搜索最长不下降序列划分逗号，然后贪心。贪心时注意：只要某一位被预置，并且与之前的string在该位不同，那么就可以对后面的数位置0.还有一些细节，比如开头不能为0。

string ans; class IncreasingLists { int lst[30]; string str[30], m; void print ( int n ) { for ( int i = 0; i < n; i ++ ) printf ( "%d ", lst[i] ); printf ( "/n" ); } void check ( int num ) { //print ( num ); string temp = ""; string last, cur; int len = 0; for ( int i = 0; i < num; i ++ ) { if ( i ) temp += ','; cur.resize ( lst[i], ' ' ); if ( lst[i] > len ) { len = lst[i]; cur[0] = str[i][0] == '?' ? '1' : str[i][0]; for ( int j = 1; j < len; j ++ ) { cur[j] = str[i][j] == '?' ? '0' : str[i][j]; } } else if ( lst[i] == len ) { int pos, j; for ( pos = 0; pos < len; pos ++ ) { if ( str[i][pos] != '?' && str[i][pos] != last[pos] ) break; } for ( j = pos; j < len; j ++ ) cur[j] = str[i][j] == '?' ? '0' : str[i][j]; int less = 1; if ( pos < len && cur[pos] > last[pos] ) less = 0; for ( j = pos - 1; j >= 0; j -- ) { if ( str[i][j] != '?' ) { cur[j] = str[i][j]; } else { if ( less ) { cur[j] = last[j] + 1; if ( cur[j] > '9' ) cur[j] = '0', less = 1; else less = 0; } else cur[j] = last[j]; } } if ( less ) return; } if ( cur[0] == '0' ) return; last = cur; temp += cur; } if ( ans.size () == 0 || temp < ans ) ans = temp; } void dfs ( int last, int cur, int len, int num, string sub ) { if ( m.size () - last - 1 < len ) return; if ( cur == m.size () ) { int tlen = cur - last - 1; if ( tlen >= len ) { lst[num] = tlen; str[num ++] = sub; //print ( num ); check ( num ); } return; } int tlen = cur - last - 1; if ( m[cur] == ',' ) { if ( tlen >= len ) { lst[num] = tlen; str[num] = sub; dfs ( cur, cur + 1, tlen, num + 1, "" ); } return; } if ( m[cur] >= '0' && m[cur] <= '9' ) { dfs ( last, cur + 1, len, num, sub + m[cur] ); return; } if ( tlen >= len ) { lst[num] = tlen; str[num] = sub; dfs ( cur, cur + 1, tlen, num + 1, "" ); } dfs ( last, cur + 1, len, num, sub + m[cur] ); } public: string makeIncreasingList(string mask) { m = mask; ans = ""; dfs ( -1, 0, 1, 0, "" ); if ( ans.size () == 0 ) return "impossible"; else return ans; } }