为什么有问题啊，求解，找了好久都没找出来

#include <stdio.h>
#define N 40
int readscore(int score[]);
int mian()
{
int score[N],n;
n = readscore(score);
printf("不及格人数:%d\n",n);
return 0;
}
int readscore(int score[])
{
int m=0,i=-1;
do{
i++;
printf("input score:");
scanf("%d",&score[i]);
if (score[i] <= 59 && score[i]>=0)
m++;
printf("\n");
}while (score[i]>=0);
return m;
}