No valid executable file was produced by the compiler /tmp/compiler_90dg0866/src: 在函数‘main’中: /tmp/compiler_90dg0866/src:6:17: 警告：格式 ‘%c’ expects argument of type ‘char ’, but argument 2 has type ‘char ()[1000]’ [-Wformat=] 6 | scanf("%c", &M); | ~^ ~~ | | | | | char ()[1000] | char * /tmp/compiler_90dg0866/src:7:17: 警告：格式 ‘%c’ expects argument of type ‘char ’, but argument 2 has type ‘char ()[1000]’ [-Wformat=] 7 | scanf("%c", &N); | ~^ ~~ | | | | | char ()[1000] | char * /tmp/compiler_90dg0866/src:16:17: 警告：隐式声明函数‘itoa’ [-Wimplicit-function-declaration] 16 | itoa(j, crr, 10); | ^~~~ /nix/store/js66s0xwjnzg0ggi2lq9bcvlk6x2za13-binutils-2.35.2/bin/ld: ./ccBBskqP.o: in function main': src:(.text+0xa9): undefined reference to itoa' collect2: 错误：ld 返回 1