SPOJ Problem 3923:Philosophers Stone

#include<cstdio>
#include<cstring>
int t,i,j,n,m,s,a[105][105],f[105][105];
int max(int a,int b){return a>b?a:b;}
int main(){
    scanf("%d",&t);
    while(t--){
        scanf("%d%d",&n,&m);
        for (i=1;i<=n;i++)
            for (j=1;j<=m;j++)
                scanf("%d",&a[i][j]);
        memset(f,0,sizeof(f));
        for(i=1;i<=n;i++)
            for (j=1;j<=m;j++){
                f[i][j]=max(max(f[i-1][j],f[i-1][j-1]),f[i-1][j+1])+a[i][j];
            }
        s=0;
        for (i=1;i<=m;i++)
            if (s<f[n][i])s=f[n][i];
        printf("%d\n",s);
    }
}