The Triangle
时间限制:1000 ms | 内存限制:65535 KB
难度:4
- 描述
7
3 8
8 1 0
2 7 4 4
4 5 2 6 5
(Figure 1)
Figure 1 shows a number triangle. Write a program that calculates the highest sum of numbers passed on a route that starts at the top and ends somewhere on the base. Each step can go either diagonally down to the left or diagonally down to the right.
- 输入
- Your program is to read from standard input. The first line contains one integer N: the number of rows in the triangle. The following N lines describe the data of the triangle. The number of rows in the triangle is > 1 but <= 100. The numbers in the triangle, all integers, are between 0 and 99. 输出
- Your program is to write to standard output. The highest sum is written as an integer. 样例输入
5 7 3 8 8 1 0 2 7 4 4 4 5 2 6 5
样例输出30
自底向上进行计算。
利用一个新的数组先存储三角形最后一行的值,然后上一行存储最后一行的各值与上一行左右相加的较大值,
以此类推,最后在三角形的定点的得到路径最大值。
#include<iostream>
#include<algorithm>
using namespace std;
int tri[105][105], cal[105][105];
int main()
{
int n;
cin >> n;
for(int i = 1; i <= n; i++)
for(int j = 1; j <= i; j++)
cin >> tri[i][j];
for(int j = 1; j <= n; j++)
cal[n][j] = tri[n][j];
for(int i = n - 1; i >= 1; i--)
for(int j = 1; j <= i; j++)
cal[i][j] = tri[i][j] + max(cal[i + 1][j], cal[i + 1][j + 1]);
cout << cal[1][1] << endl;
return 0;
}