数列分段 II

题目描述

思路

代码

#include <cstdio>

int n, m, arr[100005], ans;
int l, r, mid, inf = 0x7f3f3f3f;
inline int read() {
	int s = 0, f = 1;
	char ch = getchar();
	while (ch < '0' || ch > '9') {
		if (ch == '-') f = -1;
		ch = getchar();
	}
	while (ch >= '0' && ch <= '9') s = s * 10 + ch - '0', ch = getchar();
	return s * f;
	return 0;
}
bool valid(int x) {
	int cnt = 0, sum = 0;
	for (int i = 1; i <= n; ++i) {
		if (arr[i] > x) return false;
		if (sum + arr[i] <= x) sum += arr[i];
		else cnt++, sum = arr[i];
	}
	if (sum != 0) cnt++;
	return cnt <= m;
}

int main() {
	n = read(), m = read();
	for (int i = 1; i <= n; ++i) arr[i] = read();
	l = 0, r = inf;
	while (l <= r) {
		mid = l + r >> 1;
		if (valid(mid)) ans = mid, r = mid - 1;
		else l = mid + 1;
	}
	printf("%d", ans);
	return 0;
}