请问为什么我的总分和平均分显示不出来？

#include <stdio.h>

#define N

int allScore(int score[])

{

    int i;

int sum = 0;

for (i = 0; i<10; i++)

{

sum += score[i];

return sum;

}

printf("学生的总分为%d\n", sum);

printf("学生平均分为%d\n", sum / 10);

return 0;

}

int maxminScore(int score[])

{

int i, j, k;

for (i = 9; i>0; i--)

{

for (j = 0; j<i; j++)

{

if (score[j]<score[j + 1])

{

k = score[j];

score[j] = score[j + 1];

score[j + 1] = k;

}

}

}

printf("学生最高分%d\n", score[0]);

printf("学生最低分%d\n", score[9]);

for (i = 0; i<10; i++)

{

printf("%d\n", score[i]);

}

return 0;

}

int main()

{

int score[N] = { 67,98,75,63,82,79,81,91,66,84 };

allScore(score);

maxminScore(score);

return 0;

}