B - The Triangle

        7      3   8    8   1   0  2   7   4   44   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.         Input       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.        Output       Your program is to write to standard output. The highest sum is written as an integer.       Sample Input
573 88 1 0 2 7 4 44 5 2 6 5Sample Output
30
题目意思：从顶端往下加求最大的那一条路。
思路可以采用逆向思维的方法，用替换。举个例子，以上的为例，第四行2+4>2+5,7+5>7+2.......然后就变成了
        7      3   8    8   1   0
   7  12  10 10
依次类推求出最大。
代码：
#include<cstdio>#define Max 105using namespace std;int main(){    int a[Max][Max];    int i,j,n;    while(~scanf("%d",&n))    {        for(i=0;i<n;i++)        {            for(j=0;j<=i;j++)            {                scanf("%d",&a[i][j]);            }        }        for(i=n-2;i>=0;i--)        {            for(j=0;j<=i;j++)            {                a[i][j]+=a[i+1][j]>a[i+1][j+1]?a[i+1][j]:a[i+1][j+1];            }        }        printf("%d/n",a[0][0]);    }    return 0;}