Question

我希望从特定字符串中获取所有数字，但是，这些数字可能超过一位数为（15,587，... exc）。这就是我所做的＆＃34;我自己的代码＆＃34;：

int firstIndxOfNumb(char* str, int startIndx, int len) {
    int i, val;
    i = startIndx;
    while (str[i] && i < len) {
        val = str[i];
        if (isdigit(val))
            return i;
        i++;
    }
    return -1;
}

int lastIndxOfNumb(char* exp, int len, int indx1){
    int i, curr;
    for(i = indx1; i < len; i++){
        curr = exp[i];
        if(!isdigit(curr)){
            return --i;
        }
    }
    return 0;
}

int getNumb(char* exp, int len, int* indx1){
    int indx2 = lastIndxOfNumb(exp, len, *indx1);

    printf("indx1:%d\tindx2:%d\n", *indx1, indx2);

    char temp[indx2-*indx1];
    strncpy(temp, exp+*indx1, (size_t) (indx2-*indx1+1));
    *indx1 = firstIndxOfNumb(exp, indx2+1, len);
    return atoi(temp);
}

void main() {
    char *s = "())(15*59";
    int len = strlen(s);
    int indx1;
    indx1 = firstIndxOfNumb(s, 0, len);
    printf("%d\n", getNumb(s, len, &indx1));
    printf("\n%d", getNumb(s, len, &indx1));

}

目标是得到两个数字（15,59）。第一个电话是好的，但第二个电话不是＆＃34;无限循环＆＃34;值 index1：7 好吧 index2：0 不行！你能帮我把它搞定.....你这些值由printf(..);函数中的getNum();打印....

Answer 1

getNumb可以简化如下。

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

int getNumb(char **sp){
    char *p = *sp;
    while(*p && !isdigit((unsigned char)*p))//skip not digit
        ++p;
    if(!*p)
        return -1;//not find numbers (Don't include negative numbers as extract numbers)
    int ret = strtol(p, &p, 10);
    *sp = p;
    return ret;
}

int main(void) {
    char *s = "())(15*59";
    char *sp = s;
    printf("%d\n", getNumb(&sp));
    printf("%d\n", getNumb(&sp));
}

当它包含负数时。

#include <stdio.h>
#include <stdlib.h>
#include <ctype.h>
#include <stdbool.h>

bool getNum(char **sp, int *v /* out */){
    char *p = *sp;
    while(*p && !isdigit((unsigned char)*p) && (*p!='-' || !isdigit((unsigned char)p[1])) )//skip not number
        ++p;
    if(!*p)
        return false;//not find numbers
    *v = strtol(p, &p, 10);
    *sp = p;
    return true;
}

int main(void) {
    char *s = "())(15*59+++-123,-2)";
    char *sp = s;
    int v;
    while(getNum(&sp, &v))
        printf("%d\n", v);
}

从C中的字符串中提取所有N个数字

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