题解 | 计算某字符出现次数

#include <ctype.h>
#include <stdio.h>
#include <string.h>

int main() {
    char s[10000] = {0};
    char c;
    fgets(s, 100000, stdin);//scanf只能接收不含空格的字符
    scanf("%c", &c);
    int ret = 0;

    if (isdigit(c)) {
        for (int i = 0; i < strlen(s); i++) {
            if (c == s[i]) {
                ret++;
            }
        }
    } else {
        if (c > 90) {//统一转为小写
            c -= 32;
        }

        for (int i = 0; i < strlen(s); i++) {
            if (c == s[i] || c == (s[i] - 32)) {
                ret++;
            }
        }
    }

    printf("%d", ret);
    return 0;
}