n^2的算法就行,很简单的动态规划。直接上代码
/* * Author : ben */ #include <cstdio> #include <cstdlib> #include <cstring> #include <cmath> #include <ctime> #include <iostream> #include <algorithm> #include <queue> #include <set> #include <map> #include <stack> #include <string> #include <vector> #include <deque> #include <list> #include <functional> #include <numeric> #include <cctype> using namespace std; /* * 输入非负整数 * 支持short、int、long、long long等类型(修改typec即可)。 * 用法typec a = get_int();返回-1表示输入结束 */ typedef int typec; typec get_int() { typec res = 0, ch; while (!((ch = getchar()) >= ‘0‘ && ch <= ‘9‘)) { if (ch == EOF) return -1; } res = ch - ‘0‘; while ((ch = getchar()) >= ‘0‘ && ch <= ‘9‘) res = res * 10 + (ch - ‘0‘); return res; } //输入整数(包括负整数,故不能通过返回值判断是否输入到EOF,本函数当输入到EOF时,返回-1),用法int a = get_int2(); int get_int2() { int res = 0, ch, flag = 0; while (!((ch = getchar()) >= ‘0‘ && ch <= ‘9‘)) { if (ch == ‘-‘) flag = 1; if (ch == EOF) return -1; } res = ch - ‘0‘; while ((ch = getchar()) >= ‘0‘ && ch <= ‘9‘) res = res * 10 + (ch - ‘0‘); if (flag == 1) res = -res; return res; } /** * 输入一个字符串到str中,与scanf("%s", str)类似, * 会忽略掉缓冲区中的空白字符。返回值为输入字符串 * 的长度,返回-1表示输入结束。 */ int get_str(char *str) { char c; while ((c = getchar()) <= ‘ ‘) { if(c == EOF) { return -1; } } int I = 0; while (c > ‘ ‘) { str[I++] = c; c = getchar(); } str[I] = 0; return I; } const int MAXN = 1010; int data[MAXN], f[MAXN]; int N; int main() { while ((N = get_int()) > 0) { for (int i = 0; i < N; i++) { data[i] = get_int2(); } f[0] = data[0]; for (int i = 1; i < N; i++) { int ma = 0; for (int j = i - 1; j >= 0; j--) { if (data[j] < data[i] && f[j] > ma) { ma = f[j]; } } f[i] = ma + data[i]; } printf("%d\n", *max_element(f, f + N)); } return 0; }
时间: 2024-10-05 23:50:19