题解 | #字符统计#

C题解：

简单直观

typedef struct CharInfo {
    char c;
    int count;
} CharInfo;

int main() {
    char s[1000];
    while(scanf("%s", s) != -1) {
        int len = strlen(s);
        CharInfo infos[1000];
        int infoCount = 0;
        for(int i = 0; i < len; i++) {
            char c = s[i];
            int index = -1;
            for(int j = 0; j < infoCount; j++) {
                CharInfo info = infos[j];
                if(info.c == c) {
                    index = j;
                    break;
                }
            }
            CharInfo info;
            if(index != -1) {
                info = infos[index];
                info.count += 1;
                infos[index] = info;
            } else {
                info.c = c;
                info.count = 1;
                infos[infoCount] = info;
                infoCount++;
            }
        }
        for(int i = 0; i < infoCount; i++) {
            for(int j = i + 1; j < infoCount; j++) {
                CharInfo info1 = infos[i];
                CharInfo info2 = infos[j];
                if(info1.count < info2.count) {
                    infos[i] = info2;
                    infos[j] = info1;
                } else if(info1.count == info2.count) {
                    if(info1.c > info2.c) {
                        infos[i] = info2;
                        infos[j] = info1;
                    }
                }
            }
        }
        char result[infoCount + 1];
        for(int i = 0; i < infoCount; i++) {
            result[i] = infos[i].c;
        }
        result[infoCount] = '\0';
        printf("%s\n", result);
    }
    return 0;
}