given length and sum of digits
time limit per test
1 second
memory limit per test
256 megabytes
input
standard input
output
standard output
you have a positive integer m and a non-negative integer s. your task is to find the smallest and the largest of the numbers that have length m and sum of digits s. the required numbers should be non-negative integers written in the decimal base without leading zeroes.
input
the single line of the input contains a pair of integers m, s (1?≤?m?≤?100,?0?≤?s?≤?900) ? the length and the sum of the digits of the required numbers.
output
in the output print the pair of the required non-negative integer numbers ? first the minimum possible number, then ? the maximum possible number. if no numbers satisfying conditions required exist, print the pair of numbers -1 -1 (without the quotes).
sample test(s)
input
2 15
output
69 96
input
3 0
output
-1 -1
题意：给两个数m, s，求出位数等于m 且个位数字之和等于s的最小数和最大数。
解题思路：直接贪心的去构造。先判断输出-1，-1的情况：m*9
ac代码：
#include #include #include #include #include #include #include #include #include #include #include #include using namespace std;#define inf 0x7fffffffint a[105], b[105];int main(){// freopen(in.txt,r,stdin); int m, s; while(scanf(%d%d, &m, &s)!=eof) { if(!s && m==1) {printf(0 0\n); continue; } //m == 1 && s == 0 if(s > m*9 || s == 0) { //构造不成功的情况 cout0; i--){ int x = min(ss, 9); b[i] = x; ss -= x; } if(ss) b[0] += ss; for(int i=0; i