標準入力から一行づつ読み込み最大値を表示(Cの場合)

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

int main(){

    int max;
    char buf[1000];
    char* num;
    int flag = 0;
    
    while(fgets(buf, 1000,stdin) != NULL){
        num = strtok(buf," \n");
        while(num != NULL){
            if(flag == 0 || max < atoi(num)){
                flag = 1;
                max = atoi(num);
            }
            num =strtok(NULL,"\n");
        }
    }
    printf("%d\n",max);
    return 0;
}