USACO:Score Inflation解题报告

思路：完全背包问题，DP状态转移方程，一维的：f[j] = max(f[j],f[j-time[i]]+score[i])

 

 

/*
ID: xpli1
PROG: inflate
LANG: C
*/

#include <stdio.h>
#include <math.h>
#include <ctype.h>
#include <stdlib.h>

#define max(a,b) (((a) > (b)) ? (a) : (b))
#define min(a,b) (((a) < (b)) ? (a) : (b))

#define INT_MAX 0x7fffffff
#define IN stdin
#define OUT stdout
#define MAX_SIZE  10001

int score[MAX_SIZE];
int time[MAX_SIZE];
int f[MAX_SIZE];
int M,N;

int main(void)
{
 FILE* fin = fopen("inflate.in","r");
 FILE* fout = fopen("inflate.out","w");

 fscanf(IN,"%d%d",&M,&N);

 int i,j;

 f[0] = 0;
 for(i=0; i<N; i++){
  fscanf(IN,"%d%d",&score[i],&time[i]);
  for(j=time[i]; j<=M; j++){
    f[j] = max(f[j],f[j-time[i]]+score[i]);
  }
 }

 fprintf(OUT,"%d/n",f[M]);
 return 0;
}