foo.c: In function 'main':
foo.c:5:9: warning: statement with no effect [-Wunused-value]
    5 |         for(j;j<n;j++) {
      |         ^~~
foo.c:6:17: warning: statement with no effect [-Wunused-value]
    6 |                 for(k;k<i;k++){
      |                 ^~~
foo.c:9:17: warning: statement with no effect [-Wunused-value]
    9 |                 for(x;x<n-i;x++){
      |                 ^~~

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