C語言編程：輸入壹大寫字符，將它轉換成小寫字符輸出。 急求！要編程程序

void main()

{

char a[]={'a','b','c','d','e','f','g','h','i','j','k','l','m','n','o','p','q','r','s','t','u','v','w','x','y','z'};

char b[]={'A','B','C','D','E','F','G','H','I','J','K','L','M','N','O','P','Q','R','S','T','U','V','W','X','Y','Z'};

char c;int i;

printf("請輸入壹個大寫字母");

scanf("%c",&c);

for(i=0;i<26;i++)

{

if(c==b[i])

{

c=a[i];

break;

}

}

printf("小寫是%c",c);

}