题解 | #找出字符串中第一个只出现一次的字符#

#import <Foundation/Foundation.h>

int main(int argc, char* argv[]) {
    NSAutoreleasePool* pool = [[NSAutoreleasePool alloc] init];

    char str[1000];
    gets(str);

    int len = strlen(str);
    int a[1000] = {0};

    for (int i = 0; i < len; i++) {
        a[str[i]]++;
    }
    for (int i = 0; i < len; i++) {
        if (a[str[i]] == 1) {
            printf("%c\n", str[i]);
            break;
        }
        if (i == len - 1) {
            printf("-1\n");
            break;
        }
    }

    [pool drain];
    return 0;
}