POJ 3273 Monthly Expense 二分枚举
题目：http://poj.org/problem?id=3273
二分枚举，据说是经典题，看了题解才做的，暂时还没有完全理解。。
1 #include <stdio.h> 2 #include <string.h> 3 4 int n, m; 5 int a[100000]; 6 7 bool judge(int x) 8 { 9 int money = 0, cnt = 1; 10 for(int i = 0; i < n; i++) 11 { 12 if(money + a[i] <= x) 13 money += a[i]; 14 else 15 { 16 money = a[i]; 17 cnt++; 18 } 19 } 20 if(cnt > m) 21 return 0; 22 else return 1; 23 } 24 25 int main() 26 { 27 int low = 0, high = 0; 28 scanf("%d %d", &n, &m); 29 for(int i = 0; i < n; i++) 30 { 31 scanf("%d", &a[i]); 32 if(low < a[i]) 33 low = a[i]; 34 high += a[i]; 35 } 36 int mid = (low + high) / 2; 37 while(low < high) 38 { 39 if(judge(mid)) 40 high = mid - 1; 41 else low = mid + 1; 42 mid = (low + high) / 2; 43 } 44 printf("%d\n", mid); 45 return 0; 46 }
