杭电ACM FatMouse' Trade算法题

杭电ACM FatMouse' Trade算法题
Problem Description
FatMouse prepared M pounds of cat food, ready to trade with the cats guarding the warehouse containing his favorite food, JavaBean.The warehouse has N rooms. The i-th room contains J[i] pounds of JavaBeans and requires F[i] pounds of cat food. FatMouse does not have to trade for all the JavaBeans in the room, instead, he may get J[i]* a% pounds of JavaBeans if he pays F[i]* a% pounds of cat food. Here a is a real number. Now he is assigning this homework to you: tell him the maximum amount of JavaBeans he can obtain.

Input
The input consists of multiple test cases. Each test case begins with a line containing two non-negative integers M and N. Then N lines follow, each contains two non-negative integers J[i] and F[i] respectively. The last test case is followed by two -1's. All integers are not greater than 1000.

Output
For each test case, print in a single line a real number accurate up to 3 decimal places, which is the maximum amount of JavaBeans that FatMouse can obtain.
Sample Input
5 37 24 35 2-1 -1
Sample Output
13.333

我的代码,请问哪里有错啊,谢谢
#include
int main(){
int m,i,j,k;
float rate,sum,ji,fi,t,n;
while(scanf("%f%d",&n,&m)&&n+1||m+1){
k=3*m,sum=0;
float a[k];
for(i=0;i