查找字符串中的单词并替换

/* The string is: To do or not to do, It is a question! Enter your want to find a character string: not Enter you want to replace a character string: and To do or not to do, It is a question! To do or and to do, It is a question! 替换的单词必须与原单词长度相同，长度不同的情况实例如下： The string is: To do or not to do, It is a question!Enter your want to find a character string: doEnter you want to replace a character string: killTo do or not to do, It is a question!Tokil or not tokil, It is a question! */#include <stdio.h>#include <string.h>char * Find(char *, const char *, const char *, int);void Replace(char *, const char *, int);int main(void) {    int lenB = 4,  lenC = 4, ch, i;    char a[] = "To do or not to do, It is a question!";    char b[lenB];    char c[lenC];    printf("Enter your want to find a character string: ");    for (i = 0; (ch = getchar()) != '\n'; i++){        if (i < lenB)            b[i] = ch;        else            printf("Not enough space, The character stirng is too long !");    }    printf("Enter you want to replace a character string: ");    for (i = 0; (ch = getchar()) != '\n'; i++){        if (i < lenC)            c[i] = ch;        else            printf("Not enough space, The character stirng is too long !");    }    printf("%s\n", a);    Find(a, b, c, lenC - 1);    printf("%s", a);    return 0;}char * Find(char * a, const char * b, const char * c, int cLen){    char * pApear = NULL;    const char * pB;    while (*a++){        for (pB = b; *pB; pB++){            if (*a != *pB)                break;            else                a++;        }        if (*pB == '\0'){            pApear = a;            Replace(a-1, c, cLen-1);        }    }    return pApear;}void Replace(char * a, const char * c, int cLen){    while (cLen > -1)        *a-- = c[cLen--];    return;}