bzoj1668

做水题有助身心健康 :
细节处理

#include<bits/stdc++.h>using namespace std;inline int read(void) {    int x = 0, c, f = 1;    do {c=getchar();if(c=='-')f=-1;}while(c<'0'||c>'9');    do {x=x*10+c-'0';c=getchar();}while(c>='0'&&c<='9');    return x * f;}const int N = 110;int a[N][N], f[N][N], n, m;int main(){    n = read(), m = read();    for (int i = 1; i <= n; i++)         for (int j = 1; j <= m; j++)            a[i][j] = read();    f[1][1] = a[1][1];    for (int j = 1; j < m; j++)        for (int i = 1; i <= n; i++) if (f[i][j]){            f[i][j] += a[i][j];            f[i][j+1] = max(f[i][j+1], f[i][j]);            f[i+1][j+1] = max(f[i+1][j+1], f[i][j]);            f[i-1][j+1] = max(f[i-1][j+1], f[i][j]);        }    cout << f[n][m] + a[n][m] - a[1][1]<< endl;     }