Question

请告诉我每次循环输入时如何正确使用fgets。由于我的for循环只工作一次然后程序中断。我也尝试过使用buffer和getc，但似乎没什么用。

    #include <stdio.h>
    #include <string.h>
    #include <stdlib.h>
    int main(void){
        int k,i,j,t,n,m;
        char buffer[100];
        fgets(buffer,100,stdin);
        sscanf(buffer,"%d",&t);
        while(t--){
            char buffer1[100];
            fgets(buffer1,100,stdin);
            sscanf(buffer1,"%d%d",&n,&m);
            char pattern[n+1][m+1];
            for(i=0;i<n;i++){
                fgets(pattern[i],m,stdin);
            }
        }
    }
    /* My OUTPUT:
2
2 3
RGR
GRR
3 4
Process returned 0 (0x0)   execution time : 8.106 s
Press any key to continue.
where as I wanted this:
2
2 3
RGR  (this is just random input
GRR   )
3 4 
RRGG (this is just random input
GRRR
RGGG  )
*/

Answer 1

你仍然没有足够的防守功能，所以如果它们中的任何一个失败你就可以抓住它。我会说检查函数的返回值和几个关于函数中使用的参数的检查。

#include<stdio.h>
#include<stdlib.h>
int main(void){
    int t;
    char buffer[100];
    if( fgets(buffer,100,stdin) == NULL ){
        fprintf(stderr, "%s\n", "Input Error using fgets");
        exit(1);
    }
    if( sscanf(buffer,"%d",&t) != 1){
        fprintf(stderr, "%s\n", "Input Error using sscanf");
        exit(1);
    }
    if( t < 0 ){
        fprintf(stderr, "%s\n","Error in inputting t" );
        exit(1);
    }
    while(t--){
        char buffer1[100];
        if( fgets(buffer,100,stdin) == NULL ){
            fprintf(stderr, "%s\n", "Input Error using fgets");
            exit(1);
        }
        int n,m;   
        if( sscanf(buffer1,"%d%d",&n,&m) == 2){
            fprintf(stderr, "%s\n", "Input Error using sscanf");
            exit(1);       
        }

        if(!( n && m) ){
            fprintf(stderr, "%s\n", "Error in input n,m" );
            exit(1);
        }
        char pattern[n+1][m+1];
        for(size_t i=0;i<n;i++){
            if( fgets(pattern[i],m,stdin)== NULL){
                fprintf(stderr, "%s\n","Error in input" );
                exit(1);
            }
        }
    }
    return 0;
}

是否有永久的解决方案

1 个答案: