数字三角形 Number Triangles--动态规划

版权声明：转载请附上地址 https://blog.csdn.net/weixin_44574520/article/details/89555213

luogu 1216

Code:

#include <bits/stdc++.h>
using namespace std;
#define maxn 1010

int n,a[maxn][maxn],f[maxn][maxn];

inline void init_() {
	freopen("a.txt","r",stdin);
}

inline int read_() {
	int x=0,f=1;
	char c=getchar();
	while(c<'0'||c>'9') {
		if(c=='-') f=-1;
		c=getchar();
	}
	while(c>='0'&&c<='9') {
		x=x*10+c-'0';
		c=getchar();
	}
	return x*f;
}

inline void readda_() {
	n=read_();
	for(int i=1;i<=n;i++) {
		for(int j=1;j<=i;j++) {
			a[i][j]=read_();
		}
	}
}

inline void clean_() {
	memset(f,0,sizeof(f));
}

inline void work_() {
	int maxd=0;
	clean_();
	for(int i=1;i<=n;i++) {
		for(int j=1;j<=i;j++) {
			f[i][j]=max(f[i-1][j]+a[i][j],f[i-1][j-1]+a[i][j]);
			if(i==n) maxd=max(f[i][j],maxd);
		}
	}
	printf("%d",maxd);
}

int main() {
	init_();
	readda_();
	work_();
	return 0;
}